WO2011163016A2

WO2011163016A2 - Processes using molecular sieve ssz-81

Info

Publication number: WO2011163016A2
Application number: PCT/US2011/040374
Authority: WO
Inventors: Stacey I. Zones; Anna Jackowski
Original assignee: Chevron U.S.A. Inc.
Priority date: 2010-06-25
Filing date: 2011-06-14
Publication date: 2011-12-29
Also published as: WO2011163016A3

Abstract

The present invention is directed to processes using a new crystalline molecular sieve designated SSZ-81, which is synthesized using a structure directing agent selected from 1,5-bis(1-azonia-bicyclo[2.2.2]octane)pentane dications, 1,5-bis(1,4-diazabicyclo[2.2.2]octane)pentane dications, and mixtures thereof.

Description

PROCESSES USING MOLECULAR SIEVE SSZ-81

This application claims the benefit of U.S. Provisional Application 61/358,807 filed

06/25/10.

FIELD OF THE INVENTION

The present invention relates to processes using new molecular sieve SSZ-81, wherein the molecular sieve is synthesized in a hydroxide media using a structure directing agent ("SDA") selected from l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane dications, l,5-bis(l,4- diazabicyclo[2.2.2]octane)pentane dications, and mixtures thereof.

BACKGROUND OF THE INVENTION

Molecular sieves are a class of important materials used in the chemical industry for processes such as gas stream purification and hydrocarbon conversion processes. Molecular sieves are porous solids having interconnected pores of different sizes. Molecular sieves typically have a one-, two- or three-dimensional crystalline pore structure having pores of one or more molecular dimensions that selectively adsorb molecules that can enter the pores, and exclude those molecules that are too large. The pore size, pore shape, interstitial spacing or channels, composition, crystal morphology and structure are a few characteristics of molecular sieves that determine their use in various hydrocarbon adsorption and conversion processes.

For the petroleum and petrochemical industries, the most commercially useful molecular sieves are known as zeolites. A zeolite is an aluminosilicate having an open framework structure formed from corner sharing the oxygen atoms of [Si0₄] and [A10₄] tetrahedra or silica and alumina octahedra. Mobile extra framework cations reside in the pores for balancing charges along the zeolite framework. These charges are a result of substitution of a tetrahedral framework cation (e.g. Si⁴⁺) with a trivalent or pentavalent cation. Extra framework cations counter-balance these charges preserving the

electroneutrality of the framework, and these cations are exchangeable with other cations and/or protons. Synthetic molecular sieves, particularly zeolites, are typically synthesized by mixing sources of alumina and silica in an aqueous media, often in the presence of a structure directing agent or templating agent. The structure of the molecular sieve formed is determined in part by solubility of the various sources, silica-to-alumina ratio, nature of the cation, synthesis conditions (temperature, pressure, mixing agitation), order of addition, type of templating agent, and the like.

Although many different crystalline molecular sieves have been discovered, there is a continuing need for new molecular sieves with desirable properties for gas separation and drying, hydrocarbon and chemical conversions, and other applications. New molecular sieves may contain novel internal pore architectures, providing enhanced selectivities in these processes.

SUMMARY OF THE INVENTION

The present invention is directed to a new family of molecular sieves with unique properties, referred to herein as "molecular sieve SSZ-81" or simply "SSZ-81."

In accordance with the present invention there is provided a molecular sieve having a mole ratio greater than about 10 of silicon oxide to aluminum oxide and having, after calcination, the powder X-ray diffraction (XRD) lines of Table 4.

The present invention further includes a method for preparing a crystalline material by contacting under crystallization conditions: (1) at least one source of silicon; (2) at least one source of aluminum; (3) at least one source of an element selected from Groups 1 and 2 of the Periodic Table; (4) hydroxide ions; and (5) a structure directing agent selected from 1,5- bis( 1 -azonia-bicyclo[2.2.2]octane)pentane dications, 1 ,5-bis( 1 ,4- diazabicyclo[2.2.2]octane)pentane dications, and mixtures thereof.

The present invention also includes a process for preparing a molecular sieve having, after calcination, the powder XRD lines of Table 4, by:

(a) preparing a reaction mixture containing: (1) at least one source of silicon; (2) at least one source of aluminum; (3) at least one source of an element selected from Groups 1 and 2 of the Periodic Table; (4) hydroxide ions; (5) a structure directing agent selected from l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane dications, l,5-bis(l,4- diazabicyclo[2.2.2]octane)pentane dications, and mixtures thereof; and (6) water; and (b) maintaining the reaction mixture under conditions sufficient to form crystals of the molecular sieve.

Where the molecular sieve formed is an intermediate material, the process of the present invention includes a further post-synthesis processing in order to achieve the target molecular sieve (e.g. by acid leaching in order to achieve a higher silica to alumina (Si:Al) ratio).

The present invention also provides a novel molecular sieve designated SSZ-81 having, as-synthesized and in the anhydrous state, in terms of mole ratios, as follows:

Broadest Secondary

Si0₂ / Al₂0₃ 10 - 60 20 - 35

(Q + A) / Si0₂ 0.02 - 0.10 0.04 - 0.07

M / Si0₂ 0.01 - 1.0 0.02 - 0.04

wherein:

(1) M is selected from the group consisting of elements from Groups 1 and 2 of the Periodic Table;

(2) Q is at least one l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane dication structure directing agent, and Q > 0; and

(3) A is at least one l,5-bis(l,4-diazabicyclo[2.2.2]octane)pentane dication structure directing agent, and A > 0.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows the results of powder X-ray diffraction (XRD) analysis of the as- synthesized molecular sieve prepared in Example 1.

Figure 2 shows the results of a scanning electron microscopy (SEM) analysis of the calcined molecular sieve of Example 2.

DETAILED DESCRIPTION OF THE INVENTION

Introduction

The term "Periodic Table" refers to the version of IUPAC Periodic Table of the Elements dated June 22, 2007, and the numbering scheme for the Periodic Table Groups is as described in Chemical and Engineering News, 63(5), 27 (1985). The term "molecular sieve" includes (a) intermediate and (b) final or target molecular sieves and molecular sieves produced by (1) direct synthesis or (2) post-crystallization treatment (secondary synthesis). Secondary synthesis techniques allow for the synthesis of a target material having a higher Si:Al ratio from an intermediate material by acid leaching or other similar dealumination methods.

Where permitted, all publications, patents and patent applications cited in this application are herein incorporated by reference in their entirety, to the extent such disclosure is not inconsistent with the present invention.

Unless otherwise specified, the recitation of a genus of elements, materials or other components, from which an individual component or mixture of components can be selected, is intended to include all possible sub-generic combinations of the listed components and mixtures thereof. Also, "include" and its variants, are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that may also be useful in the materials, compositions and methods of this invention.

Reaction Mixture

The present invention is directed to a molecular sieve designated herein as "molecular sieve SSZ-81" or simply "SSZ-81."

In preparing SSZ-81, a l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane dication, a 1,5- bis(l,4-diazabicyclo[2.2.2]octane)pentane dication, or a mixture thereof, is used as a structure directing agent ("SDA"), also known as a crystallization template. The SDAs useful for making SSZ-81 are represented by the following structures (1) and (2):

l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane dication

(2)

1 ,5-bis( 1 ,4-diazabicyclo [2.2.2] octane)pentane dication

In general, SSZ-81 is prepared by:

(a) preparing a reaction mixture containing (1) at least one source of silicon; (2) at least one source of aluminum; (3) at least one source of an element selected from Groups 1 and 2 of the Periodic Table; (4) hydroxide ions; and (5) a structure directing agent selected from l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane dications, l,5-bis(l,4- diazabicyclo[2.2.2]octane)pentane dications, and mixtures thereof; and

(b) maintaining the reaction mixture under conditions sufficient to form crystals of the molecular sieve.

Where the molecular sieve formed is an intermediate material, the process of the present invention includes a further step of synthesizing a target molecular sieve by post- synthesis techniques, such as acid leaching.

The composition of the reaction mixture from which the molecular sieve is formed, in terms of molar ratios, is identified in Table 1 below:

TABLE 1

Reactants Broad Secondary

S1O2 / AI2O3 molar ratio 20 - 80 25 - 35

M / S1O2 molar ratio 0.05 - 0.30 0.10 - 0.20

(Q + A) / Si0₂ molar ratio 0.05 - 0.30 0.10 - 0.20

OH^" / S1O2 molar ratio 0.20 - 0.60 0.30 - 0.35

H2O / S1O2 molar ratio 10 - 50 30 - 40 wherein compositional variables Q, A and M are as described herein above. Sources useful herein for silicon include fumed silica, precipitated silicates, silica hydrogel, silicic acid, colloidal silica, tetra-alkyl orthosilicates (e.g. tetraethyl orthosilicate), and silica hydroxides.

Sources useful for aluminum include oxides, hydroxides, acetates, oxalates, ammonium salts and sulfates of aluminum. Typical sources of aluminum oxide include aluminates, alumina, and aluminum compounds such as AICI₃, A1₂(S04)3, aluminum hydroxide (Al(OH₃)), kaolin clays, and other zeolites. An example of the source of aluminum oxide is LZ-210 and LZ-52 zeolite (types of Y zeolites).

As described herein above, for each embodiment described herein, the reaction mixture may be formed using at least one source of an element selected from Groups 1 and 2 of the Periodic Table (referred to herein as M). In one subembodiment, the reaction mixture is formed using a source of an element from Group 1 of the Periodic Table. In another subembodiment, the reaction mixture is formed using a source of sodium (Na). Any M- containing compound which is not detrimental to the crystallization process is suitable.

Sources for such Groups 1 and 2 elements include oxides, hydroxides, nitrates, sulfates, halogenides, oxalates, citrates and acetates thereof.

The SDA dication is typically associated with anions (X ) which may be any anion that is not detrimental to the formation of the zeolite. Representative anions include elements from Group 17 of the Periodic Table (e.g., fluoride, chloride, bromide and iodide), hydroxide, acetate, sulfate, tetrafluoroborate, carboxylate, and the like.

The l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane dication SDA of the present invention (represented by structure (1)) can be synthesized by reacting a dihaloalkane (such as 1,5-dibromopentane) with l-azonia-bicyclo[2.2.2]octane. The l,5-bis(l,4- diazabicyclo[2.2.2]octane)pentane dication SDA of the present invention (represented by structure (2)) can be synthesized by reacting a dihaloalkane (such as 1,5-dibromopentane) with l,4-diazabicyclo[2.2.2]octane.

For each embodiment described herein, the molecular sieve reaction mixture can be supplied by more than one source. Also, two or more reaction components can be provided by one source.

The reaction mixture can be prepared either batch wise or continuously. Crystal size, morphology and crystallization time of the molecular sieve described herein may vary with the nature of the reaction mixture and the synthesis conditions. Crystallization and Post-Synthesis Treatment

In practice, the molecular sieve is prepared by:

(a) preparing a reaction mixture as described herein above; and

(b) maintaining the reaction mixture under crystallization conditions sufficient to form the molecular sieve. (See, Harry Robson, Verified Syntheses ofZeolitic Materials, 2^nd revised edition, Elsevier, Amsterdam (2001)).

The reaction mixture is maintained at an elevated temperature until the molecular sieve is formed. The hydrothermal crystallization is usually conducted under pressure, and usually in an autoclave so that the reaction mixture is subject to autogenous pressure, at a temperature between 125°C and 200°C.

The reaction mixture may be subjected to mild stirring or agitation during the crystallization step. It will be understood by a person skilled in the art that the molecular sieves described herein may contain impurities, such as amorphous materials, unit cells having framework topologies which do not coincide with the molecular sieve, and/or other impurities (e.g., organic hydrocarbons).

During the hydrothermal crystallization step, the molecular sieve crystals can be allowed to nucleate spontaneously from the reaction mixture. The use of crystals of the molecular sieve as seed material can be advantageous in decreasing the time necessary for complete crystallization to occur. In addition, seeding can lead to an increased purity of the product obtained by promoting the nucleation and/or formation of the molecular sieve over any undesired phases. When used as seeds, seed crystals are added in an amount between 1% and 10% of the weight of the source for silicon used in the reaction mixture.

Once the molecular sieve has formed, the solid product is separated from the reaction mixture by standard mechanical separation techniques such as filtration. The crystals are water-washed and then dried to obtain the as-synthesized molecular sieve crystals. The drying step can be performed at atmospheric pressure or under vacuum.

The molecular sieve can be used as-synthesized, but typically will be thermally treated (calcined). The term "as-synthesized" refers to the molecular sieve in its form after crystallization, prior to removal of the SDA cation. The SDA can be removed by thermal treatment (e.g., calcination), preferably in an oxidative atmosphere (e.g., air, gas with an oxygen partial pressure of greater than 0 kPa) at a temperature readily determinable by one skilled in the art sufficient to remove the SDA from the molecular sieve. The SDA can also be removed by photolysis techniques (e.g. exposing the SDA-containing molecular sieve product to light or electromagnetic radiation that has a wavelength shorter than visible light under conditions sufficient to selectively remove the organic compound from the molecular sieve) as described in U.S. Patent No. 6,960,327 to Navrotsky and Parikh, issued November 1, 2005.

The molecular sieve can subsequently be calcined in steam, air or inert gas at temperatures ranging from about 200°C to about 800°C for periods of time ranging from 1 to 48 hours, or more. Usually, it is desirable to remove the extra-framework cation (e.g. Na⁺) by ion-exchange or other known method and replace it with hydrogen, ammonium, or any desired metal-ion.

Where the molecular sieve formed is an intermediate material, the target molecular sieve can be achieved using post-synthesis techniques to allow for the synthesis of a target material having a higher Si:Al ratio from an intermediate material by acid leaching or other similar dealumination methods.

The molecular sieve made from the process of the present invention can be formed into a wide variety of physical shapes. Generally speaking, the molecular sieve can be in the form of a powder, a granule, or a molded product, such as extrudate having a particle size sufficient to pass through a 2-mesh (Tyler) screen and be retained on a 400-mesh (Tyler) screen. In cases where the catalyst is molded, such as by extrusion with an organic binder, the molecular sieve can be extruded before drying, or, dried or partially dried and then extruded.

The molecular sieve catalyst of the present invention can optionally be combined with one or more catalyst supports, active base metals, other molecular sieves, promoters, and mixtures thereof. Examples of such materials and the manner in which they can be used are disclosed in U.S. Patent No. 4,910,006, issued May 20, 1990 to Zones et al, and U.S. Patent No. 5,316,753, issued May 31, 1994 to Nakagawa.

Catalyst supports combinable with SSZ-81 include alumina, silica, zirconia, titanium oxide, magnesium oxide, thorium oxide, beryllium oxide, alumina-silica, amorphous alumina-silica, alumina-titanium oxide, alumina-magnesium oxide, silica-magnesium oxide, silica-zirconia, silica-thorium oxide, silica-beryllium oxide, silica-titanium oxide, titanium oxide-zirconia, silica-alumina-zirconia, silica-alumina-thorium oxide, silica-alumina-titanium oxide or silica-alumina-magnesium oxide, preferably alumina, silica-alumina, clays, and combinations thereof.

Exemplary active base or noble metals useful herein include those selected from the elements from Group 6 through Group 10 of the Periodic Table, their corresponding oxides and sulfides, and mixtures thereof. In one subembodiment, each base or noble metal is selected from the group consisting of nickel (Ni), palladium (Pd), platinum (Pt), cobalt (Co), iron (Fe), rhenium (Re), chromium (Cr), molybdenum (Mo), tungsten (W), and mixtures thereof. In another subembodiment, the hydroprocessing catalyst contains at least one Group 6 base metal and at least one base metal selected from Groups 8 through 10 of the periodic table. Exemplary metal combinations include Ni/Mo/W, Mi/Mo, Mo/W, Co/Mo, Co/W and W/Ni.

Promoters include those selected from phosphorous (P), boron (B), silicon (Si), aluminum (Al), and mixtures thereof.

SSZ-81 is useful in catalysts for a variety of hydrocarbon conversion reactions such as hydrocracking, fluidized catalytic cracking (FCC), hydroisomerization, dewaxing, olefin isomerization, alkylation of aromatic compounds and the like. SSZ-81 is also useful as an adsorbent for separations.

In one embodiment, SSZ-81 is used in a hydroisomerization process which includes the step of contacting SSZ-81, typically in the hydrogen form containing a noble metal such as platinum, palladium or a mixture thereof, with a feed containing C₄ - C7 linear and branched paraffins, under hydroisomerization conditions. In one particular subembodiment, a hydroisomerization process is provided which includes the step of contacting molecular sieve SSZ-81 based catalyst with a feed containing C₄ - C7 linear and branched paraffins, under hydroisomerization conditions sufficient to yield a liquid product having a higher research octane number (RON), as determined by ASTM D2699-09, than the feed.

The feed is typically a light straight run fraction, boiling within the range of 30°F to 250°F (-1°C to 121°C), for example from 60°F to 200°F (16°C to 93°C). The isomerization reaction is typically carried out in the presence of hydrogen. Hydrogen may be added to give a hydrogen-to-hydrocarbon ratio (¾/HC) of between 0.5 and 10 H2/HC, for example between 1 and 8 H₂/HC. Typically, the feed is contacted with SSZ-81 (or a catalyst containing SSZ-81) at a temperature in the range of from about 150°F to about 700°F (65.5°C to 371°C), at a pressure ranging from about 50 psig to about 2000 psig (0.345 MPa to 13.8 MPa), and a feed liquid hour space velocity (LHSV) ranging from about 0.5 to about 5 h^"1.

See U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753 for a further discussion of isomerization process conditions.

A low sulfur feed is useful in the present process. The feed desirably contains less than 10 ppm, for example less than 1 ppm or less than 0.1 ppm sulfur. In the case of a feed which is not already low in sulfur, acceptable levels can be reached by hydrogenating the feed in a presaturation zone with a hydrogenating catalyst which is resistant to sulfur poisoning. See the aforementioned U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753 for a further discussion of this hydrodesulfurization process.

It is typical to limit the nitrogen level and the water content of the feed. Catalysts and processes which are suitable for these purposes are known to those skilled in the art.

After a period of operation, the catalyst can become deactivated by sulfur or coke.

See the aforementioned U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753 for a further discussion of methods of removing this sulfur and coke, and of regenerating the catalyst.

The conversion catalyst desirably contains one or more Group 8 - 10 metals. The Group 8 - 10 noble metals and their compounds, platinum, palladium, and iridium, or combinations thereof can be used. Rhenium and tin may also be used in conjunction with the noble metal. Typically, the metal is platinum or palladium. The amount of Group 8 - 10 metal present in the conversion catalyst should be within the normal range of use in hydroisomerizing catalysts, from about 0.05 to 2.0 weight percent, for example 0.2 to 0.8 weight percent.

Characterization of the Molecular Sieve

Molecular sieves made by the process of the present invention have a composition, as- synthesized and in the anhydrous state, as described in Table 2 (in terms of mole ratios), wherein compositional variables Q, A and M are as described herein above.

TABLE 2

Broadest Secondary

Si0₂ / Al₂0₃ 10 - 60 20 - 35

(Q + A) / Si0₂ 0.02 - 0.10 0.04 - 0.07 M / Si0₂ 0.01 - 1.0 0.02 - 0.04

Molecular sieves synthesized by the process of the present invention are characterized by their XRD pattern. The powder XRD pattern lines of Table 3 are representative of as- synthesized SSZ-81 made in accordance with this invention. Minor variations in the diffraction pattern can result from variations in the mole ratios of the framework species of the particular sample due to changes in lattice constants. In addition, sufficiently small crystals will affect the shape and intensity of peaks, leading to significant peak broadening. Minor variations in the diffraction pattern can also result from variations in the organic compound used in the preparation and from variations in the Si/Al mole ratio from sample to sample. Calcination can also cause minor shifts in the XRD pattern. Notwithstanding these minor perturbations, the basic crystal lattice structure remains unchanged.

TABLE 3

Characteristic Peaks for As-Synthesized SSZ-81

2 Theta^(a) d-spacing (Angstroms) Relative Intensity (%)^(b)

7.02 12.58 W

7.41 1 1.91 M

7.41 peak - 10.50^(c) W, broad band

18.50 - 22.03 peak^(d) W, broad band

22.03 4.03 W - M

22.58 3.94 S

23.30 3.81 W

24.12 3.69 W

25.10 3.55 W

27.30 3.26 W

28.55 3.12 W (^a) ± 0.20

^(h) The powder XRD patterns provided are based on a relative intensity scale in which the strongest line in the X-ray pattern is assigned a value of 100: W(weak) is less than 20; M(medium) is between 20 and 40; S(strong) is between 40 and 60; VS(very strong) is greater than 60. ^(c>' ⁽ ' In the pattern for as-synthesized SSZ-81, it can be seen that there is a first low- intensity (W), broad-band running from the peak near 2Θ = 7.4 degrees down to baseline at near 2Θ = 10.5 degrees, and a second low-intensity, broad-band rising from the baseline at about 2Θ = 18.5 degrees and then merging into a well-defined peak just beyond 22 degrees. This behavior is seen in all samples of as-synthesized SSZ-81.

The X-ray diffraction pattern lines of Table 4 are representative of calcined SSZ-81 made in accordance with this invention.

TABLE 4

Characteristic Peaks for Calcined SSZ-81

2 Theta^(a) d-spacing (Angstroms) Relative Intensity (%)^(b)

7.45 1 1.86 S

7.45 peak - 10.50^(c) W, broad band

14.38 6.15 W

18.50 - 22.26 peak^(d) W, broad band

22.26 3.99 W

22.79 3.90 S

23.53 3.78 W-M

24.36 3.65 W-M

25.37 3.51 W

26.37 3.38 W

27.53 3.24 W

28.67 3.1 1 W

^(a) ± 0.20

' The powder XRD patterns provided are based on a relative intensity scale in which the strongest line in the X-ray pattern is assigned a value of 100: W(weak) is less than 20; M(medium) is between 20 and 40; S(strong) is between 40 and 60; VS(very strong) is greater than 60.

(< ^> (d) j_n p_afl-_em f_or calcined SSZ-81, it can be seen that there is a first low- intensity (W), broad-band running from the peak near 2Θ = 7.4 degrees down to baseline at near 2Θ = 10.5 degrees, and a second low-intensity, broad-band rising from the baseline at about 2Θ = 18.5 degrees and then merging into a well-defined peak just beyond 22 degrees. This behavior is seen in all samples of calcined SSZ-81.

The powder X-ray diffraction patterns presented herein were collected by standard techniques. The radiation was CuK-a radiation. The peak heights and the positions, as a function of 2Θ where Θ is the Bragg angle, were read from the relative intensities of the peaks (adjusting for background), and d, the interplanar spacing in Angstroms corresponding to the recorded lines, can be calculated. Hydrocarbon Conversion Processes

The SSZ-81 molecular sieve of this invention is useful as catalyst in a wide range of hydrocarbon conversion processes. Hydrocarbon conversion reactions are chemical and catalytic processes in which carbon containing compounds are changed to different carbon containing compounds. Specific examples of hydrocarbon conversion processes which are effectively catalyzed by SSZ-81, by itself or in combination with one or more other catalytically active substances including other crystalline catalysts, include hydrocracking, dewaxing, catalytic cracking, aromatics formation, isomerization, alkylation and

transalkylation, conversion of paraffins to aromatics, isomerization of olefins, xylene isomerization, oligomerization, condensation of alcohols, methane upgrading and polymerization of 1 -olefins.

The SSZ-81 catalysts may have high selectivity, and under hydrocarbon conversion conditions can provide a high percentage of desired products relative to total products.

For high catalytic activity, the SSZ-81 molecular sieve should be predominantly in its hydrogen form. Generally, the molecular sieve is converted to its hydrogen form by ammonium exchange followed by calcination. If the molecular sieve is synthesized with a high enough ratio of SDA cation to sodium ion, calcination alone may be sufficient.

Typically, after calcination at least 80% of the cation sites are occupied by hydrogen ions and/or rare earth ions. As used herein, "predominantly in the hydrogen form" means that, after calcination, at least 80% of the cation sites are occupied by hydrogen ions and/or rare earth ions.

Molecular sieve SSZ-81 can be used in processing hydrocarbonaceous feedstocks. Hydrocarbonaceous feedstocks contain carbon compounds and can be from many different sources, such as virgin petroleum fractions, recycle petroleum fractions, shale oil, liquefied coal, tar sand oil, synthetic paraffins from NAO, and recycled plastic feedstocks. Other feeds include synthetic feeds, such as those derived from a Fischer-Tropsch process, including an oxygenate-containing Fischer-Tropsch process boiling below about 371°C (700°F). In general, the feed can be any carbon containing feedstock susceptible to zeolitic catalytic reactions. Depending on the type of processing the hydrocarbonaceous feed is to undergo, the feed can contain one or more metals or be free of metals; it can also have high or low nitrogen or sulfur impurities. It can be appreciated, however, that in general processing will be more efficient (and the catalyst more active) the lower the metal, nitrogen, and sulfur content of the feedstock.

The conversion of hydrocarbonaceous feeds can take place in any convenient mode, for example, in a fluidized bed, moving bed, or fixed bed reactor, depending on the type of process employed. The formulation of the catalyst particles will vary depending on the conversion process and method of operation.

Other reactions which can be performed using the catalyst of this invention containing a metal, e.g., an element selected from Groups 8 - 10 of the Periodic Table such platinum, include hydrogenatiow-dehydrogenation reactions, denitrogenation and desulfurization reactions.

The following Table 5 indicates typical reaction conditions which may be employed when using catalysts comprising SSZ-81 in the hydrocarbon conversion reactions of this invention. Typical conditions are indicated in parentheses.

TABLE 5

Process Temp.,°C Pressure LHSV

Hydrocracking 175-485 0.5-350 bar 0.1-30

Dewaxing 200-475 15-3000 psig, 0.1-20

(250-450) 0.103-20.7 Mpa (0.2-10)

gauge

(200-3000, 1.38-

20.7 Mpa gauge)

Aromatics 400-600 atm.-ΙΟ bar 0.1-15

formation (480-550)

Cat. Cracking 127-885 subatm.-¹ 0.5-50 (atm.-5 atm.)

Oligomerization 232-649² 0.1-50 atm.²'³ 0.2-50²

10-232⁴ 0.05-20⁵

(27-204)⁴ (0.1-10)⁵

Paraffins to 100-700 0-1000 psig 0.5-40⁵

aromatics

Condensation of 260-538 0.5-1000 psig, 0.5-50⁵

alcohols 0.00345-6.89 Mpa

gauge

Isomerization 93-538 50-1000 psig, 1-10

(204-315) 0.345-6.89 Mpa (1-4)

gauge

Xylene 260-593² 0.5-50 atm.² 0.1-100⁵

isomerization (315-566)² (1-5 atm)² (0.5-50)⁵

38-371⁴ 1-200 atm.⁴ 0.5-50

¹ Several hunc red atmospheres

² Gas phase reaction

³ Hydrocarbon partial pressure

⁴ Liquid phase reaction

⁵ WHSV

Other reaction conditions and parameters are provided below. Hydrocracking

Using a catalyst which comprises SSZ-81, for example predominantly in the hydrogen form, and a hydrogenation promoter, heavy petroleum residual feedstocks, cyclic stocks and other hydrocrackate charge stocks can be hydrocracked using the process conditions and catalyst components disclosed in U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753.

The hydrocracking catalysts contain an effective amount of at least one hydrogenation component of the type commonly employed in hydrocracking catalysts. The hydrogenation component is generally selected from the group of hydrogenation catalysts consisting of one or more metals of Groups 6 - 10, including the salts, complexes and solutions containing such. The hydrogenation catalyst may be selected from the group of metals, salts and complexes thereof of the group consisting of at least one of platinum, palladium, rhodium, iridium, ruthenium, and mixtures thereof, or at least one of nickel, molybdenum, cobalt, tungsten, titanium, chromium and mixtures thereof. Reference to the catalytically active metal or metals is intended to encompass such metal or metals in the elemental state or in some form such as an oxide, sulfide, halide, carboxylate and the like. The hydrogenation catalyst is present in an effective amount to provide the hydrogenation function of the hydrocracking catalyst, for example in the range of from 0.05 to 25% by weight.

Dewaxing

SSZ-81, for example predominantly in the hydrogen form, can be used to dewax hydrocarbonaceous feeds by selectively removing straight chain paraffins. Typically, the viscosity index of the dewaxed product is improved (compared to the waxy feed) when the waxy feed is contacted with SSZ-81 under isomerization dewaxing conditions.

The catalytic dewaxing conditions are dependent in large measure on the feed used and upon the desired pour point. Hydrogen is typically present in the reaction zone during the catalytic dewaxing process. The hydrogen to feed ratio is typically between about 500 and about 30,000 SCF/bbl (standard cubic feet per barrel) (0.089 to 5.34 SCM liter (standard cubic meters/liter)), for example about 1000 to about 20,000 SCF/bbl (0.178 to 3.56 SCM/liter). Generally, hydrogen will be separated from the product and recycled to the reaction zone. Typical feedstocks include light gas oil, heavy gas oils and reduced crudes boiling above about 350°F (177°C).

A typical dewaxing process is the catalytic dewaxing of a hydrocarbon oil feedstock boiling above about 350°F (177°C) and containing straight chain and slightly branched chain hydrocarbons by contacting the hydrocarbon oil feedstock in the presence of added hydrogen gas at a hydrogen pressure of about 15-3000 psi (0.103-20.7 Mpa) with a catalyst containing SSZ-81 and at least one Group 8 - 10 metal.

The SSZ-81 hydrodewaxing catalyst may optionally contain a hydrogenation component of the type commonly employed in dewaxing catalysts. See the aforementioned U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753 for examples of these

hydrogenation components.

The hydrogenation component is present in an effective amount to provide an effective hydrodewaxing and hydroisomerization catalyst for example in the range of from about 0.05 to 5% by weight. The catalyst may be run in such a mode to increase

isomerization dewaxing at the expense of cracking reactions.

The feed may be hydrocracked, followed by dewaxing. This type of two stage process and typical hydrocracking conditions are described in U.S. Patent No. 4,921,594, issued May 1, 1990 to Miller.

SSZ-81 may also be utilized as a dewaxing catalyst in the form of a combination of catalysts. The combination comprises a first catalyst comprising molecular sieve SSZ-81 and, desirably, at least one metal selected from Groups 8 - 10 of the Periodic Table, and a second catalyst comprising an aluminosilicate zeolite which is more shape selective than molecular sieve SSZ-81. As used herein, the term "combination" includes mixtures of the molecular sieve of this invention and the aluminosilicate zeolite, layers of the molecular sieve and zeolite, or any other configuration in which the feed comes in contact with both the molecular sieve and the zeolite. The use of combined catalysts in the form of layers is disclosed in U.S. Patent No. 5,149,421, issued September 22, 1992 to Miller. The layering may also include a bed of SSZ-81 layered with a non-zeolitic component designed for either hydrocracking or hydrofinishing.

SSZ-81 may also be used to dewax raffinates, including bright stock, under conditions such as those disclosed in U.S. Patent No. 4, 181,598, issued January 1, 1980 to Gillespie et al.

It is often desirable to use mild hydrogenation (sometimes referred to as

hydrofinishing) to produce more stable dewaxed products. The hydrofinishing step can be performed either before or after the dewaxing step, typically after. Hydrofinishing is typically conducted at temperatures ranging from about 190°C to about 340°C at pressures from about 400 psig to about 3000 psig (2.76 to 20.7 Mpa gauge) at space velocities (LHSV) between about 0.1 and 20 and a hydrogen recycle rate of about 400 to 1500 SCF/bbl (0.071 to 0.27 SCM/liter). The hydrogenation catalyst employed must be active enough not only to hydrogenate the olefins, diolefins and color bodies which may be present, but also to reduce the aromatic content. Suitable hydrogenation catalyst are disclosed in U.S. Patent

No. 4,921,594, issued May 1, 1990 to Miller. The hydrofinishing step is beneficial in preparing an acceptably stable product (e.g., a lubricating oil) since dewaxed products prepared from hydrocracked stocks tend to be unstable to air and light and tend to form sludges spontaneously and quickly. Lube oil may be prepared using SSZ-81. For example, a C2₀+ lube oil may be made by isomerizing a C2₀+ olefin feed over a catalyst containing SSZ-81 in the hydrogen form and at least one metal selected from Groups 8 - 10 of the Periodic Table. Alternatively, the lubricating oil may be made by hydrocracking in a hydrocracking zone a hydrocarbonaceous feedstock to obtain an effluent comprising a hydrocracked oil, and catalytically dewaxing the effluent at a temperature of at least about 400°F (204°C) and at a pressure of from about 15 psig to about 3000 psig (0.103-20.7 Mpa gauge) in the presence of added hydrogen gas with a catalyst containing SSZ-81 in the hydrogen form and at least one metal selected from Groups 8 - 10 of the Periodic Table.

Aromatics Formation

SSZ-81 can be used to convert light straight run naphthas and similar mixtures to highly aromatic mixtures. Thus, normal and slightly branched chained hydrocarbons, for example those having a boiling range above about 40°C and less than about 200°C, can be converted to products having a substantial higher octane aromatics content by contacting the hydrocarbon feed with a catalyst containing SSZ-81. It is also possible to convert heavier feeds into BTX or naphthalene derivatives of value using a catalyst containing SSZ-81.

The conversion catalyst typically contains a Group 8 - 10 metal compound to have sufficient activity for commercial use. By Group 8 - 10 metal compound as used herein is meant the metal itself or a compound thereof. The Group 8 - 10 noble metals and their compounds, platinum, palladium, and iridium, or combinations thereof can be used.

Rhenium or tin or a mixture thereof may also be used in conjunction with the Group 8 - 10 metal compound (typically a noble metal compound), for example a platinum compound. The amount of Group 8 - 10 metal present in the conversion catalyst should be within the normal range of use in reforming catalysts, from about 0.05 to 2.0 weight percent, for example 0.2 to 0.8 weight percent.

It is critical to the selective production of aromatics in useful quantities that the conversion catalyst be substantially free of acidity, for example, by neutralizing the molecular sieve with a basic metal, e.g., alkali metal, compound. Methods for rendering the catalyst free of acidity are known in the art. See the aforementioned U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753 for a description of such methods. Typical alkali metals are sodium, potassium, rubidium and cesium. The molecular sieve itself can be substantially free of acidity only at very high silica to alumina mole ratios.

Catalytic Cracking

Hydrocarbon cracking stocks can be catalytically cracked in the absence of hydrogen using SSZ-81, for example predominantly in the hydrogen form.

When SSZ-81 is used as a catalytic cracking catalyst in the absence of hydrogen, the catalyst may be employed in conjunction with traditional cracking catalysts, e.g., any aluminosilicate heretofore employed as a component in cracking catalysts. Typically, these are large pore, crystalline aluminosilicates. Examples of these traditional cracking catalysts are disclosed in the aforementioned U.S. Patent No. 4,910,006 and U.S. Patent No 5,316,753.

When a traditional cracking catalyst (TC) component is employed, the relative weight ratio of the TC to the SSZ-81 is generally between about 1 : 10 and about 500: 1, desirably between about 1 : 10 and about 200: 1, for example between about 1 :2 and about 50: 1 or between about 1 : 1 and about 20: 1. The novel molecular sieve and/or the traditional cracking component may be further ion exchanged with rare earth ions to modify selectivity.

The cracking catalysts are typically employed with an inorganic oxide matrix component. See the aforementioned U.S. Patent No. 4,910,006 and U.S. Patent

No. 5,316,753 for examples of such matrix components.

Isomerization

The present catalyst is highly active and highly selective for isomerizing C₄ to C7 hydrocarbons. The activity means that the catalyst can operate at relatively low temperature which thermodynamically favors highly branched paraffins. Consequently, the catalyst can produce a high octane product. The high selectivity means that a relatively high liquid yield can be achieved when the catalyst is run at a high octane.

In one embodiment, SSZ-81 is used in a hydroisomerization process which includes the step of contacting SSZ-81, typically in the hydrogen form containing a noble metal such as platinum, palladium or a mixture thereof, with a feed containing C₄ - C7 linear and branched paraffins, under hydroisomerization conditions. In one particular subembodiment, a hydroisomerization process is provided which includes the step of contacting molecular sieve SSZ-81 based catalyst with a feed containing C₄ - C7 linear and branched paraffins, under hydroisomerization conditions sufficient to yield a product having a higher research octane number (RON), as determined by ASTM D2699-09, than the feed.

The feed is typically a light straight run fraction, boiling within the range of 30°F to 250°F (-1°C to 121°C), for example from 60°F to 200°F (16°C to 93°C). The isomerization reaction is typically carried out in the presence of hydrogen. Hydrogen may be added to give a hydrogen-to-hydrocarbon ratio (H₂/HC) of between 0.5 and 10 H₂/HC, for example between 1 and 8 H₂/HC. Typically, the feed is contacted with SSZ-81 (or a catalyst containing SSZ-81) at a temperature in the range of from about 150°F to about 700°F (65.5°C to 371°C), at a pressure ranging from about 50 psig to about 2000 psig (0.345 MPa to 13.8 MPa), and a feed liquid hour space velocity (LHSV) ranging from about 0.5 to about 5 h^"1. See U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753 for a further discussion of isomerization process conditions.

After a period of operation, the catalyst can become deactivated by sulfur or coke. See the aforementioned U.S. Patent No. 4,910,006 and U.S. Patent No. 5,316,753 for a further discussion of methods of removing this sulfur and coke, and of regenerating the catalyst.

The conversion catalyst desirably contains one or more Group 8 - 10 metals. The

Group 8 - 10 noble metals and their compounds, platinum, palladium, and iridium, or combinations thereof can be used. Rhenium and tin may also be used in conjunction with the noble metal. Typically, the metal is platinum or palladium. The amount of Group 8 - 10 metal present in the conversion catalyst should be within the normal range of use in hydroisomerizing catalysts, from about 0.05 to 2.0 weight percent, for example 0.2 to 0.8 weight percent. Alkylation and Transalkylation

SSZ-81 can be used in a process for the alkylation or transalkylation of an aromatic hydrocarbon. The process comprises contacting the aromatic hydrocarbon with a C2 to Ci6 olefin alkylating agent or a polyalkyl aromatic hydrocarbon transalkylating agent, under at least partial liquid phase conditions, and in the presence of a catalyst containing SSZ-81.

SSZ-81 can also be used for removing benzene from gasoline by alkylating the benzene as described above and removing the alkylated product from the gasoline.

For high catalytic activity, the SSZ-81 molecular sieve should be predominantly in its hydrogen form. It is typical that, after calcination, at least 80% of the cation sites are occupied by hydrogen ions and/or rare earth ions.

Examples of suitable aromatic hydrocarbon feedstocks which may be alkylated or transalkylated by the process of the invention include aromatic compounds such as benzene, toluene and xylene. Benzene is especially useful. There may be occasions where naphthalene or naphthalene derivatives such as dimethylnaphthalene may be desirable. Mixtures of aromatic hydrocarbons may also be employed.

Suitable olefins for the alkylation of the aromatic hydrocarbon are those containing 2 to 20, for example 2 to 4, carbon atoms, such as ethylene, propylene, butene-1, trans-butene-2 and cis-butene-2, or mixtures thereof. There may be instances where pentenes are desirable. Typical olefins are ethylene and propylene. Longer chain alpha olefins may be used as well.

When transalkylation is desired, the transalkylating agent is a polyalkyl aromatic hydrocarbon containing two or more alkyl groups that each may have from 2 to about 4 carbon atoms. For example, suitable polyalkyl aromatic hydrocarbons include di-, tri- and tetra-alkyl aromatic hydrocarbons, such as diethylbenzene, triethylbenzene,

diethylmethylbenzene (diethyltoluene), di-isopropylbenzene, di-isopropyltoluene, dibutylbenzene, and the like. Typical polyalkyl aromatic hydrocarbons are the dialkyl benzenes. A particularly desirable polyalkyl aromatic hydrocarbon is di-isopropylbenzene.

When alkylation is the process conducted, reaction conditions are as follows. The aromatic hydrocarbon feed should be present in stoichiometric excess. It is typical that the molar ratio of aromatics to olefins be greater than 4: 1 to prevent rapid catalyst fouling. The reaction temperature may range from 100°F to 600°F (38°C to 315°C), for example 250°F to 450°F (121°C to 232°C). The reaction pressure should be sufficient to maintain at least a partial liquid phase in order to retard catalyst fouling. This is typically 50 psig to 1000 psig (0.345 to 6.89 Mpa gauge) depending on the feedstock and reaction temperature. Contact time may range from 10 seconds to 10 hours, but is usually from 5 minutes to an hour. The weight hourly space velocity (WHSV), in terms of grams (pounds) of aromatic hydrocarbon and olefin per gram (pound) of catalyst per hour, is generally within the range of about 0.5 to 50.

When transalkylation is the process conducted, the molar ratio of aromatic hydrocarbon will generally range from about 1 : 1 to 25 : 1 , and for example from about 2: 1 to 20: 1. The reaction temperature may range from about 100°F to 600°F (38°C to 315°C), but it is typically about 250°F to 450°F (121°C to 232°C). The reaction pressure should be sufficient to maintain at least a partial liquid phase, typically in the range of about 50 psig to 1000 psig (0.345 to 6.89 Mpa gauge), for example 300 psig to 600 psig (2.07 to 4.14 Mpa gauge). The weight hourly space velocity will range from about 0.1 to 10. U.S. Patent No. 5,082,990 issued on January 21 , 1992 to Hsieh, et al. describes such processes and is incorporated herein by reference.

Conversion of Paraffins to Aromatics

SSZ-81 can be used to convert light gas C2-C6 paraffins to higher molecular weight hydrocarbons including aromatic compounds. Typically, the molecular sieve will contain a catalyst metal or metal oxide wherein the metal is selected from the group consisting of Groups 3 - 14 of the Periodic Table, for example gallium, niobium, indium or zinc, in the range of from about 0.05 to 5% by weight.

Isomerization of Olefins

SSZ-81 can be used to isomerize olefins. The feed stream is a hydrocarbon stream containing at least one C₄ - Ce olefin, for example a C₄ - Ce normal olefin such as normal butene. Normal butene as used in this specification means all forms of normal butene, e.g., 1-butene, cis-2-butene, and trans-2 -butene. Typically, hydrocarbons other than normal butene or other C₄ - Ce normal olefins will be present in the feed stream. These other hydrocarbons may include, e.g., alkanes, other olefins, aromatics, hydrogen, and inert gases.

The feed stream typically may be the effluent from a fluid catalytic cracking unit or a methyl-tert-butyl ether unit. A fluid catalytic cracking unit effluent typically contains about 40-60 weight percent normal butenes. A methyl-tert-butyl ether unit effluent typically contains 40-100 weight percent normal butene. The feed stream typically contains at least about 40 weight percent normal butene, for example at least about 65 weight percent normal butene. The terms iso-olefin and methyl branched iso-olefin may be used interchangeably in this specification.

The process is carried out under isomerization conditions. The hydrocarbon feed is contacted in a vapor phase with a catalyst containing SSZ-81. The process may be carried out generally at a temperature from about 625°F to about 950°F (329-510°C), for butenes, for example from about 700°F to about 900°F (371-482°C) or from about 350°F to about 650°F (177-343°C) for pentenes and hexenes. The pressure ranges from sub-atmospheric to about 200 psig (1.38 Mpa gauge), for example from about 15 psig to about 200 psig (0.103 to 1.38 Mpa gauge) or from about 1 psig to about 150 psig (0.00689 to 1.03 Mpa gauge).

The liquid hourly space velocity during contacting is generally from about 0.1 to about 50 hr^"1, based on the hydrocarbon feed, for example from about 0.1 to about 20 hr^"1, from about 0.2 to about 10 hr^"1, or from about 1 to about 5 hr^"1. A hydrogen/hydrocarbon molar ratio is maintained from about 0 to about 30 or higher. The hydrogen can be added directly to the feed stream or directly to the isomerization zone. The reaction is typically substantially free of water, typically less than about two weight percent based on the feed. The process can be carried out in a packed bed reactor, a fixed bed, fluidized bed reactor, or a moving bed reactor. The bed of the catalyst can move upward or downward. The mole percent conversion of, e.g., normal butene to iso-butene is at least 10, for example at least 25 or at least 35.

Xylene Isomerization

SSZ-81 may also be useful in a process for isomerizing one or more xylene isomers in a C8 aromatic feed to obtain ortho-, meta-, and para-xylene in a ratio approaching the equilibrium value. In particular, xylene isomerization is used in conjunction with a separate process to manufacture para-xylene. For example, a portion of the para-xylene in a mixed Cs aromatics stream may be recovered by crystallization and centrifugation. The mother liquor from the crystallizer is then reacted under xylene isomerization conditions to restore ortho-, meta- and para-xylenes to a near equilibrium ratio. At the same time, part of the

ethylbenzene in the mother liquor is converted to xylenes or to products which are easily separated by filtration. The isomerate is blended with fresh feed and the combined stream is distilled to remove heavy and light by-products. The resultant Cs aromatics stream is then sent to the crystallizer to repeat the cycle.

Optionally, isomerization in the vapor phase is conducted in the presence of 3.0 to 30.0 moles of hydrogen per mole of alkylbenzene (e.g., ethylbenzene). If hydrogen is used, the catalyst should comprise about 0.1 to 2.0 wt.% of a hydrogenation/dehydrogenation component selected from Group 8 - 10 (of the Periodic Table) metal component, especially platinum or nickel. By Group 8 - 10 metal component is meant the metals and their compounds such as oxides and sulfides.

Optionally, the isomerization feed may contain 10 to 90 wt. percent of a diluent such as toluene, trimethylbenzene, naphthenes or paraffins.

Oligomerization

SSZ-81 can also be used to oligomerize straight and branched chain olefins having from about 2 to 21, for example 2-5, carbon atoms. The oligomers which are the products of the process are medium to heavy olefins which are useful for both fuels, i.e., gasoline or a gasoline blending stock and chemicals.

The oligomerization process is accomplished by contacting the olefin feedstock in the gaseous or liquid phase with a catalyst containing SSZ-81.

The molecular sieve can have the original cations associated therewith replaced by a wide variety of other cations according to techniques well known in the art. Typical cations would include hydrogen, ammonium and metal cations including mixtures of the same. Of the replacing metallic cations, cations of metals such as rare earth metals, manganese, calcium, as well as metals of Group 2 of the Periodic Table, e.g., zinc, and Group 8 - 10 of the Periodic Table, e.g., nickel are particularly desirable. One of the prime requisites is that the molecular sieve have a fairly low aromatization activity, i.e., in which the amount of aromatics produced is not more than about 20% by weight. This is accomplished by using a molecular sieve with controlled acid activity [alpha value] of from about 0.1 to about 120, for example from about 0.1 to about 100, as measured by its ability to crack w-hexane.

Alpha values are defined by a standard test known in the art, e.g., as shown in U.S. Patent No. 3,960,978 issued on June 1, 1976 to Givens et al. If required, such molecular sieves may be obtained by steaming, by use in a conversion process or by any other method which may occur to one skilled in this art. Condensation of Alcohols

SSZ-81 can be used to condense lower aliphatic alcohols having 1 to 10 carbon atoms to a gasoline boiling point hydrocarbon product containing mixed aliphatic and aromatic hydrocarbons. The process disclosed in U.S. Patent No. 3,894, 107, issued July 8, 1975 to Butter et al, describes the process conditions used in this process.

The catalyst may be in the hydrogen form or may be base exchanged or impregnated to contain ammonium or a metal cation complement, typically in the range of from about 0.05 to 5% by weight. The metal cations that may be present include any of the metals of the Groups 1 - 10 of the Periodic Table. However, in the case of Group 1 metals, the cation content should in no case be so large as to effectively inactivate the catalyst, nor should the exchange be such as to eliminate all acidity. There may be other processes involving treatment of oxygenated substrates where a basic catalyst is desired. Methane Upgrading

Higher molecular weight hydrocarbons can be formed from lower molecular weight hydrocarbons by contacting the lower molecular weight hydrocarbon with a catalyst containing SSZ-81 and a metal or metal compound capable of converting the lower molecular weight hydrocarbon to a higher molecular weight hydrocarbon. Examples of such reactions include the conversion of methane to C2+ hydrocarbons such as ethylene or benzene or both. Examples of useful metals and metal compounds include lanthanide and or actinide metals or metal compounds.

These reactions, the metals or metal compounds employed and the conditions under which they can be run are disclosed in U.S. Patent Nos. 4,734,537, issued March 29, 1988 to Devries et al.; 4,939,31 1, issued July 3, 1990 to Washecheck et al; 4,962,261, issued October 9, 1990 to Abrevaya et al; 5,095,161, issued March 10, 1992 to Abrevaya et al; 5,105,044, issued April 14, 1992 to Han et al; 5,105,046, issued April 14, 1992 to Washecheck;

5,238,898, issued August 24, 1993 to Han et al; 5,321,185, issued June 14, 1994 to van der Vaart; and 5,336,825, issued August 9, 1994 to Choudhary et al.

Polymerization of 1-Olefins The molecular sieve of the present invention may be used in a catalyst for the polymerization of 1 -olefins, e.g., the polymerization of ethylene. To form the olefin polymerization catalyst, the molecular sieve as hereinbefore described is reacted with a particular type of organometallic compound. Organometallic compounds useful in forming the polymerization catalyst include trivalent and tetravalent organotitanium and

organochromium compounds having alkyl moieties and, optionally, halo moieties. In the context of the present invention the term "alkyl" includes both straight and branched chain alkyl, cycloalkyl and alkaryl groups such as benzyl.

Examples of trivalent and tetravalent organochromium and organotitanium compounds are disclosed in U.S. Patent No. 4,376,722, issued March 15, 1983 to Chester et al, U.S. Patent No. 4,377,497, issued March 22, 1983 to Chester et al., U.S. Patent No. 4,446,243, issued May 1, 1984 to Chester et al, and U.S. Patent No. 4,526,942, issued July 2, 1985 to Chester et al.

Examples of the organometallic compounds used to form the polymerization catalyst include, but are not limited to, compounds corresponding to the general formula (1):

MAlk_xHal_m._x (1)

wherein M is a metal selected from titanium and chromium; Alk is an alkyl; Hal is an element selected from Group 17 of the Periodic Table (e.g., CI or Br); x is 1-4; and m is greater than or equal to x and is 3 or 4.

Examples of organotitanium and organochromium compounds encompassed by such a formula include compounds of the formula CrAhQ, CrAlk₃, CrAlksHal, CrAlk₂Hal, CrAlk₂Hal₂, CrAlkHal₂, CrAlkHal₃, TiAll^, TiAlk₃, TiAlk₃Hal, TiAlk₂Hal, TiAlk₂Hal₂, TiAlkHal₂, TiAlkHal₃ , wherein Hal can be CI or Br and Alk can be methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec -butyl, tert-butyl, pentyl, isopentyl, neopentyl, hexyl, isohexyl, neohexyl, 2-ethybutyl, octyl, 2-ethylhexyl, 2,2-diethylbutyl, 2-isopropyl-3-methylbutyl, etc., cyclohexylalkyls such as, for example, cyclohexylmethyl, 2-cyclohexylethyl, 3- cyclyhexylpropyl, 4-cyclohexylbutyl, and the corresponding alkyl-substituted cyclohexyl radicals as, for example, (4-methylcyclohexyl)methyl, neophyl, i.e., beta, beta-dimethyl- phenethyl, benzyl, ethylbenzyl, and p-isopropylbenzyl. Desirable examples of Y include C1-5 alkyl, especially butyl. The organotitanium and organochromium materials employed in the catalyst can be prepared by techniques well known in the art. See, for example the aforementioned Chester et al. patents.

The organotitanium or organochromium compounds can be used with the molecular sieve of the present invention, such as by reacting the organometallic compound and the molecular sieve, in order to form the olefin polymerization catalyst. Generally, such a reaction takes place in the same reaction medium used to prepare the organometallic compound under conditions which promote formation of such a reaction product. The molecular sieve can simply be added to the reaction mixture after formation of the organometallic compound has been completed. Molecular sieve is added in an amount sufficient to provide from about 0.1 to 10 parts by weight, for example from about 0.5 to 5 parts by weight, of organometallic compound in the reaction medium per 100 parts by weight of molecular sieve.

Temperature of the reaction medium during reaction of organometallic compound with molecular sieve is also maintained at a level which is low enough to ensure the stability of the organometallic reactant. Thus, temperatures in the range of from about -150°C to 50°C, for example from about -80°C to 0°C can be usefully employed. Reaction times of from about 0.01 to 10 hours, more for example from about 0.1 to 1 hour, can be employed in reacting the organotitanium or organochromium compound with the molecular sieve.

Upon completion of the reaction, the catalyst material so formed may be recovered and dried by evaporating the reaction medium solvent under a nitrogen atmosphere.

Alternatively, olefin polymerization reactions can be conducted in this same solvent based reaction medium used to form the catalyst.

The polymerization catalyst can be used to catalyze polymerization of 1 -olefins. The polymers produced using the catalysts of this invention are normally solid polymers of at least one mono- 1 -olefin containing from 2 to 8 carbon atoms per molecule. These polymers are normally solid homopolymers of ethylene or copolymers of ethylene with another mono- 1 -olefin containing 3 to 8 carbon atoms per molecule. Exemplary copolymers include those of ethylene/propylene, ethylene/1 -butene, ethylene/ 1-hexane, and ethylene/ 1-octene and the like. The major portion of such copolymers is derived from ethylene and generally consists of about 80-99, for example 95-99 mole percent of ethylene. These polymers are well suited for extrusion, blow molding, injection molding and the like. The polymerization reaction can be conducted by contacting monomer or monomers, e.g., ethylene, alone or with one or more other olefins, and in the substantial absence of catalyst poisons such as moisture and air, with a catalytic amount of the supported organometallic catalyst at a temperature and at a pressure sufficient to initiate the

polymerization reaction. If desired, an inert organic solvent may be used as a diluent and to facilitate materials handling if the polymerization reaction is conducted with the reactants in the liquid phase, e.g. in a particle form (slurry) or solution process. The reaction may also be conducted with reactants in the vapor phase, e.g., in a fluidized bed arrangement in the absence of a solvent but, if desired, in the presence of an inert gas such as nitrogen.

The polymerization reaction is carried out at temperatures of from about 30°C or less, up to about 200°C or more, depending to a great extent on the operating pressure, the pressure of the olefin monomers, and the particular catalyst being used and its concentration. Naturally, the selected operating temperature is also dependent upon the desired polymer melt index since temperature is definitely a factor in adjusting the molecular weight of the polymer. Typically, the temperature used is from about 30°C to about 100°C in a conventional slurry or "particle forming" process or from 100°C to 150°C in a "solution forming" process. A temperature of from about 70°C to 1 10°C can be employed for fluidized bed processes.

The pressure to be used in the polymerization reactions can be any pressure sufficient to initiate the polymerization of the monomer(s) to high molecular weight polymer. The pressure, therefore, can range from subatmospheric pressures, using an inert gas as diluent, to superatmospheric pressures of up to about 30,000 psig or more, for example from

atmospheric (0 psig) up to about 1000 psig. As a general rule, a pressure of 20 to 800 psig is desirable.

The selection of an inert organic solvent medium to be employed in the solution or slurry process embodiments of this invention is not too critical, but the solvent should be inert to the supported organometallic catalyst and olefin polymer produced, and be stable at the reaction temperature used. It is not necessary, however, that the inert organic solvent medium also serve as a solvent for the polymer to be produced. Among the inert organic solvents applicable for such purposes may be mentioned saturated aliphatic hydrocarbons having from about 3 to 12 carbon atoms per molecule such as hexane, heptane, pentane, isooctane, purified kerosene and the like, saturated cycloaliphatic hydrocarbons having from about 5 to 12 carbon atoms per molecule such as cyclohexane, cyclopentane, dimethylcyclopentane and methylcyclohexane and the like and aromatic hydrocarbons having from about 6 to 12 carbon atoms per molecule such as benzene, toluene, xylene, and the like. Particularly desirable solvent media are cyclohexane, pentane, hexane and heptane.

Hydrogen can be introduced into the polymerization reaction zone in order to decrease the molecular weight of the polymers produced (i.e., give a much higher Melt Index, MI). Partial pressure of hydrogen when hydrogen is used can be within the range of 5 to 100 psig, for example 25 to 75 psig. The melt indices of the polymers produced in accordance with the instant invention can range from about 0.1 to about 70 or even higher.

More detailed description of suitable polymerization conditions including examples of particle form, solution and fluidized bed polymerization arrangements are found in

Karapinka; U.S. Patent No. 3,709,853; Issued Jan. 9, 1973 and Karol et al; U.S. Patent No. 4,086,408; Issued Apr. 25, 1978. Both of these patents are incorporated herein by reference. Hydrotreating

SSZ-81 is useful in a hydrotreating catalyst. During hydrotreatment, oxygen, sulfur and nitrogen present in the hydrocarbonaceous feed is reduced to low levels. Aromatics and olefins, if present in the feed, may also have their double bonds saturated. In some cases, the hydrotreating catalyst and hydrotreating conditions are selected to minimize cracking reactions, which can reduce the yield of the most desulfided product (typically useful as a fuel).

Hydrotreating conditions typically include a reaction temperature between 400-900°F (204-482°C), for example 650-850°F (343-454°C); a pressure between 500 and 5000 psig (3.5-34.6 Mpa), for example 1000 to 3000 psig (7.0-20.8 MPa); a feed rate (LHSV) of 0.5 hr^" ¹ to 20 hr^"1 (v/v); and overall hydrogen consumption 300 to 2000 scf per barrel of liquid hydrocarbon feed (53.4-356 m³ H2/m³ feed). The hydrotreating catalyst will typically be a composite of a Group 6 metal or compound thereof, and a Group 8 - 10 metal or compound thereof supported on the molecular sieve of this invention. Typically, such hydrotreating catalyst are presulfided.

Catalysts useful for hydrotreating hydrocarbon feeds are disclosed in U.S. Patents No.

4,347, 121, issued August 31, 1982 to Mayer et al, and 4,810,357, issued March 7, 1989 to Chester et al, both of which are incorporated herein by reference in their entirety. Suitable catalysts include noble metals from Group 8 - 10, such as Fe, Co, Ni, Pt or Pd, and/or Group 6 metals, such as Cr, Mo, Sn or W. Examples of combinations of Group 8 - 10 and Group 6 metals include Ni-Mo or Ni-Sn. Other suitable catalysts are described in U.S. Patents No. 4, 157,294, issued June 5, 1979 to Iwao et al, and 3,904,513, issued September 9, 1975 to Fischer et al. U.S. Patent No. 3,852,207, issued December 3, 1974 to Strangeland et al, describes suitable noble metal catalysts and mild hydrotreating conditions. The contents of these patents are hereby incorporated by reference.

The amount of hydrogenation component(s) in the catalyst suitably range from about 0.5% to about 10% by weight of Group 8 - 10 component(s) and from 5% to about 25% by weight of Group 6 metal component(s), calculated as metal oxide(s) per 100 parts by weight of total catalyst., where the percentages by weight are based on the weight of the catalyst before sulfiding. The hydrogenation component(s) in the catalyst may be in the oxidic and/or sulfidic form. Hydrogenation

SSZ-81 can be used in a catalyst to catalyze hydrogenation of a hydrocarbon feed containing unsaturated hydrocarbons. The unsaturated hydrocarbons can comprise olefins, dienes, polyenes, aromatic compounds and the like.

Hydrogenation is accomplished by contacting the hydrocarbon feed containing unsaturated hydrocarbons with hydrogen in the presence of a catalyst containing SSZ-81. The catalyst can also contain one or more metals of Group 6 and Group 8 - 10, including salts, complexes and solutions thereof. Reference to these catalytically active metals is intended to encompass such metals or metals in the elemental state or in some form such as an oxide, sulfide, halide, carboxylate and the like. Examples of such metals include metals, salts or complexes wherein the metal is selected from the group consisting of platinum, palladium, rhodium, iridium or combinations thereof, or the group consisting of nickel, molybdenum, cobalt, tungsten, titanium, chromium, vanadium, rhenium, manganese and combinations thereof.

The hydrogenation component of the catalyst (i.e., the aforementioned metal) is present in an amount effective to provide the hydrogenation function of the catalyst, for example in the range of from 0.05 to 25% by weight. Hydrogenation conditions, such as temperature, pressure, space velocities, contact time and the like are well known in the art.

Reduction of Oxides of Nitrogen

SSZ-81 may be used for the catalytic reduction of the oxides of nitrogen in a gas stream. Typically, the gas stream also contains oxygen, often a stoichiometric excess thereof. Also, the molecular sieve may contain a metal or metal ions within or on it which are capable of catalyzing the reduction of the nitrogen oxides. Examples of such metals or metal ions include cobalt, copper, platinum, iron, chromium, manganese, nickel, zinc, lanthanum, palladium, rhodium and mixtures thereof.

One example of such a process for the catalytic reduction of oxides of nitrogen in the presence of a zeolite is disclosed in U.S. Patent No. 4,297,328, issued October 27, 1981 to Ritscher et al. There, the catalytic process is the combustion of carbon monoxide and hydrocarbons and the catalytic reduction of the oxides of nitrogen contained in a gas stream, such as the exhaust gas from an internal combustion engine. The zeolite used is metal ion- exchanged, doped or loaded sufficiently so as to provide an effective amount of catalytic copper metal or copper ions within or on the zeolite. In addition, the process is conducted in an excess of oxidant, e.g., oxygen. Partial Oxidation of Low- Value Hydrocarbons

The partial oxidation of low- value hydrocarbons such as alkanes and alkenes into high value products such as alcohols and epoxides is of great commercial interest. These oxidation products are not only valuable as is, but also as intermediates for specialty chemicals including pharmaceuticals and pesticides.

U.S. Patent No. 4,410,501, issued October 18, 1983 to Esposito et al, discloses a titanium-containing analogue of the all-silica ZSM-5 molecular sieve. This material (known as "TS-1") has been found to be useful in catalyzing a wide range of partial oxidation chemistries, for example the production of catechol and hydroquinone from phenol and hydrogen peroxide (H2O2) and the manufacture of propylene oxide and cyclohexanone oxime from propylene and cyclohexanone, respectively. In addition, TS-1 can be used to catalyze the reaction of alkanes and aqueous H2O2 to form alcohols and ketones. (See, Huybrechts, D.R.C. et al., Nature 1990, 345, 240-242 and Tatsumi, T. et al, J. C.S. Chem. Commun. 1990, 476-477.)

TS-1 has many salient features, other than its catalytic abilities, which make it attractive as a commercial catalyst. Most importantly, it is a solid. This allows for easy separation from the reactants and products (typically liquids) by simple, inexpensive filtration. Moreover, this solid has high thermal stability and a very long lifetime.

Calcination in air at moderate temperatures (550°C) restores the material to its original catalytic ability. TS-1 performs best at mild temperatures (<100°C) and pressures (1 atm). The oxidant used for reactions catalyzed by TS-1 is aqueous ¾(¾, which is important because aqueous ¾(¾ is relatively inexpensive and its by-product is water. Hence, the choice of oxidant is favorable from both a commercial and environmental point of view.

While a catalyst system based on TS-1 has many useful features, it has one serious drawback. The zeolite structure of TS-1 includes a regular system of pores which are formed by nearly circular rings often silicon atoms (called 10-membered rings, or simply " 10 rings") creating pore diameters of approximately 5.5 A. This small size results in the exclusion of molecules larger than 5.5 A. Because the catalytically active sites are located within the pores of the zeolite, any exclusion of molecules from the pores results in poor catalytic activity.

SSZ-81 containing titanium oxide (Ti-SSZ-81) is useful as a catalyst in oxidation reactions, particularly in the oxidation of hydrocarbons. Examples of such reactions include, but are not limited to, the epoxidation of olefins, the oxidation of alkanes, and the oxidation of sulfur-containing, nitrogew-containing or phosphorus-containing compounds.

The amount of Ti-SSZ-81 catalyst employed is not critical, but should be sufficient so as to substantially accomplish the desired oxidation reaction in a practicably short period of time (i.e., a catalytically effective amount). The optimum quantity of catalyst will depend upon a number of factors including reaction temperature, the reactivity and concentration of the substrate, hydrogen peroxide concentration, type and concentration of organic solvent, as well as the activity of the catalyst. Typically, however, the amount of catalyst will be from about 0.001 to 10 grams per mole of substrate.

Typically, the Ti-SSZ-81 is thermally treated (calcined) prior to use as a catalyst.

The oxidizing agent employed in the oxidation processes of this invention is a hydrogen peroxide source such as hydrogen peroxide (H₂O₂) or a hydrogen peroxide precursor (i.e., a compound which under the oxidation reaction conditions is capable of generating or liberating hydrogen peroxide).

The amount of hydrogen peroxide relative to the amount of substrate is not critical, but must be sufficient to cause oxidation of at least some of the substrate. Typically, the molar ratio of hydrogen peroxide to substrate is from about 100: 1 to about 1 : 100, for example 10: 1 to about 1 : 10. When the substrate is an olefin containing more than one carbon-carbon double bond, additional hydrogen peroxide may be required. Theoretically, one equivalent of hydrogen peroxide is required to oxidize one equivalent of a mono-unsaturated substrate, but it may be desirable to employ an excess of one reactant to optimize selectivity to the epoxide. In particular, the use of a moderate to large excess (e.g., 50 to 200%) of olefin relative to hydrogen peroxide may be advantageous for certain substrates.

If desired, a solvent may additionally be present during the oxidation reaction in order to dissolve the reactants other than the Ti-SSZ-81, to provide better temperature control, or to favorably influence the oxidation rates and selectivities. The solvent, if present, may comprise from 1 to 99 weight percent of the total oxidation reaction mixture and is desirably selected such that it is a liquid at the oxidation reaction temperature. Organic compounds having boiling points of from about 50°C to about 150°C at atmospheric pressure are generally desirable for use. Excess hydrocarbon may serve as a solvent or diluent.

Illustrative examples of other suitable solvents include, but are not limited to, ketones (e.g., acetone, methyl ethyl ketone, acetophenone), ethers (e.g., tetrahydrofuran, butyl ether), nitriles (e.g., acetonitrile), aliphatic and aromatic hydrocarbons, halogenated hydrocarbons, and alcohols (e.g., methanol, ethanol, isopropyl alcohol, t-butyl alcohol, alpha-methyl benzyl alcohol, cyclohexanol). More than one type of solvent may be utilized. Water may also be employed as a solvent or diluent.

The reaction temperature is not critical, but should be sufficient to accomplish substantial conversion of the substrate within a reasonably short period of time. It is generally advantageous to carry out the reaction to achieve as high a hydrogen peroxide conversion as possible, typically at least about 50%, for example at least about 90% or at least about 95%, consistent with reasonable selectivities. The optimum reaction temperature will be influenced by catalyst activity, substrate reactivity, reactant concentrations, and type of solvent employed, among other factors, but typically will be in a range of from about 0°C to about 150°C (for example from about 25°C to about 120°C). Reaction or residence times from about one minute to about 48 hours (for example from about ten minutes to about eight hours) will typically be appropriate, depending upon the above-identified variables.

Although subatmospheric pressures can be employed, the reaction is typically performed at atmospheric or at elevated pressure (typically, between one and 100 atmospheres), especially when the boiling point of the substrate is below the oxidation reaction temperature.

Generally, it is desirable to pressurize the reaction vessel sufficiently to maintain the reaction components as a liquid phase mixture. Most (over 50%) of the substrate should desirably be present in the liquid phase.

The oxidation process of this invention may be carried out in a batch, continuous, or semi-continuous manner using any appropriate type of reaction vessel or apparatus such as a fixed bed, transport bed, fluidized bed, stirred slurry, or CSTR reactor. The reactants may be combined all at once or sequentially. For example, the hydrogen peroxide or hydrogen peroxide precursor may be added incrementally to the reaction zone. The hydrogen peroxide could also be generated in situ within the same reactor zone where oxidation is taking place.

Once the oxidation has been carried out to the desired degree of conversion, the oxidized product may be separated and recovered from the reaction mixture using any appropriate technique such as fractional distillation, extractive distillation, liquid-liquid extraction, crystallization, or the like. Olefin Epoxidation

One of the oxidation reactions for which Ti-SSZ-81 is useful as a catalyst is the epoxidation of olefins. The olefin substrate epoxidized in the process of this invention may be any organic compound having at least one ethylenically unsaturated functional group (i.e., a carboM-carbon double bond) and may be a cyclic, branched or straight-chain olefin. The olefin may contain aryl groups (e.g., phenyl, naphthyl). Typically, the olefin is aliphatic in character and contains from 2 to about 20 carbon atoms. The use of light (low-boiling) C2 to Cio mono-olefins is especially advantageous.

More than one carbon-carbon double bond may be present in the olefin, i.e., dienes, trienes and other polyunsaturated substrates may be used. The double bond may be in a terminal or internal position in the olefin or may alternatively form part of a cyclic structure (as in cyclooctene, for example). Other examples of suitable substrates include unsaturated fatty acids or fatty acid derivatives such as esters.

The olefin may contain substituents other than hydrocarbon substituents such as halide, carboxylic acid, ether, hydroxy, thiol, nitro, cyano, ketone, acyl, ester, anhydride, amino, and the like.

Exemplary olefins suitable for use in the process of this invention include ethylene, propylene, the butenes (i.e., 1,2-butene, 2,3-butene, isobutylene), butadiene, the pentenes, isoprene, 1-hexene, 3-hexene, 1-heptene, 1-octene, diisobutylene, 1-nonene, 1-tetradecene, pentamyrcene, camphene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1- pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, the trimers and tetramers of propylene, cyclopentene, cyclohexene, cycloheptene, cyclooctene, cyclooctadiene, dicyclopentadiene, methylenecyclopropane, methylenecyclopentane, methylenecyclohexane, vinyl cyclohexane, vinyl cyclohexene, methallyl ketone, allyl chloride, the dichlorobutenes, allyl alcohol, allyl carbonate, allyl acetate, alkyl acrylates and methacrylates, diallyl maleate, diallyl phthalate, and unsaturated fatty acids, such as oleic acid, linolenic acid, linoleic acid, erucic acid, palmitoleic acid, and ricinoleic acid and their esters (including mono-, di-, and triglyceride esters) and the like.

Olefins which are especially useful for epoxidation are the C2-C2₀ olefins having the general formula (2):

R³R⁴C=CR⁵R⁶ (2)

wherein R³, R⁴, R⁵ and R⁶ are the same or different and are selected from the group consisting of hydrogen and Ci-Cis alkyls.

Mixtures of olefins may be epoxidized and the resulting mixtures of epoxides either employed in the mixed form or separated into the different component epoxides.

The present invention further provides a process for oxidation of hydrocarbons comprising contacting the hydrocarbon with hydrogen peroxide in the presence of a catalytically effective amount of Ti-SSZ-81 for a time and at a temperature effective to oxidize the hydrocarbon. Acylation The molecular sieve of the present invention can be used in a catalyst for acylating an aromatic substrate ArH_n, where n is at least 1 , by reacting the aromatic substrate with an acylating agent in the presence of the catalyst. The product of the acylation reaction is ArH_n_iCOR where R is an organic radical.

Examples of the aromatic substrate include, but are not limited to, benzene, toluene, anisole and 2-naphthol. Examples of the acylating agent included, but are not limited to, carboxylic acid derivatives, carboxylic acids, acid anhydrides, esters, and acyl halides.

Reaction conditions are known in the art (see, for example, U.S. Patent No.

6,630,606, issued October 7, 2003 to Poliakoff et al, U.S. Patent No. 6,459,000, issued October 1, 2002 to Choudhary et al, and U.S. Patent No. 6,548,722, issued April 15, 2003 to Choudhary et al, all of which are incorporated herein by reference in their entirety).

Typically, the acylation reaction is conducted with a weight ratio of the catalyst to the acylating agent of about 0.03 to about 0.5, a mole ratio of aromatic substrate to acylating agent of about 1.0 to about 20, a reaction temperature in the range of about 20°C to about 200°C, a reaction pressure in the range of about 1 atmosphere (101.3 kPa) to about 5 atmospheres (506.6 kPa), and a reaction time of about 0.05 hours to about 20 hours.

Oxygenate Conversion

The present invention comprises a process for catalytic conversion of a feedstock comprising one or more oxygenates comprising alcohols and ethers to a hydrocarbon product containing light olefins, i.e., C₂, C3 and/or C₄ olefins. The feedstock is contacted with the molecular sieve of the present invention at effective process conditions to produce light olefins.

The term "oxygenate" as used herein designates compounds such as alcohols, ethers and mixtures thereof. Examples of oxygenates include, but are not limited to, methanol and dimethyl ether.

The process of the present invention may be conducted in the presence of one or more diluents which may be present in the oxygenate feed in an amount between about 1 and about 99 molar percent, based on the total number of moles of all feed and diluent components. Diluents include, but are not limited to, helium, argon, nitrogen, carbon monoxide, carbon dioxide, hydrogen, water, paraffins, hydrocarbons (such as methane and the like), aromatic compounds, or mixtures thereof. U.S. Patents No. 4,861,938 and 4,677,242, emphasize the use of a diluent to maintain catalyst selectivity toward the production of light olefins, particularly ethylene.

The oxygenate conversion is desirably conducted in the vapor phase such that the oxygenate feedstock is contacted in a vapor phase in a reaction zone with the molecular sieve of this invention at effective process conditions to produce hydrocarbons, i.e., an effective temperature, pressure, weight hourly space velocity (WHSV) and, optionally, an effective amount of diluent. The process is conducted for a period of time sufficient to produce the desired light olefins. In general, the residence time employed to produce the desired product can vary from seconds to a number of hours. It will be readily appreciated that the residence time will be determined to a significant extent by the reaction temperature , the molecular sieve catalyst, the WHSV, the phase (liquid or vapor) and process design characteristics. The oxygenate feedstock flow rate affects olefin production. Increasing the feedstock flow rate increases WHSV and enhances the formation of olefin production relative to paraffin production. However, the enhanced olefin production relative to paraffin production is offset by a diminished conversion of oxygenate to hydrocarbons.

The oxygenate conversion process is effectively carried out over a wide range of pressures, including autogenous pressures. At pressures between about 0.01 atmospheres (0.1 kPa) and about 1000 atmospheres (101.3 kPa), the formation of light olefins will be affected although the optimum amount of product will not necessarily be formed at all pressures. A typical pressure is between about 0.01 atmospheres (0.1 kPa) and about 100 atmospheres (10.13 kPa), for example from about 1 to about 10 atmospheres (101.3 kPa to 1.013 Mpa). The pressures referred to herein are exclusive of the diluent, if any, that is present and refer to the partial pressure of the feedstock as it relates to oxygenate compounds.

The temperature which may be employed in the oxygenate conversion process may vary over a wide range depending, at least in part, on the molecular sieve catalyst. In general, the process can be conducted at an effective temperature between about 200°C and about 700°C. At the lower end of the temperature range, and thus generally at a lower rate of reaction, the formation of the desired light olefins may become low. At the upper end of the range, the process may not form an optimum amount of light olefins and catalyst deactivation may be rapid.

The molecular sieve catalyst can be incorporated into solid particles in which the catalyst is present in an amount effective to promote the desired conversion of oxygenates to light olefins. In one aspect, the solid particles comprise a catalytically effective amount of the catalyst and at least one matrix material selected from the group consisting of binder materials, filler materials and mixtures thereof to provide a desired property or properties, e.g., desired catalyst dilution, mechanical strength and the like to the solid particles. Such matrix materials are often, to some extent, porous in nature and may or may not be effective to promote the desired reaction. Filler and binder materials include, for example, synthetic and naturally occurring substances such as metal oxides, clays, silicas, aluminas, silica- aluminas, silica-magnesias, silica-zirconias, silica-thorias and the like. If matrix materials are included in the catalyst composition, the molecular sieve desirably comprises about 1 to 99%, for example about 5 to 90% or about 10 to 80% by weight of the total composition.

Gas Separation

The molecular sieve of the present invention can be used to separate gasses. For example, it can be used to separate carbon dioxide from natural gas. Typically, the molecular sieve is used as a component in a membrane that is used to separate the gasses. Examples of such membranes are disclosed in U.S. Patent No. 6,508,860, issued January 21, 2003 to Kulkarni et al.

Synthesis of Amines

The molecular sieve of the present invention can be used in a catalyst to prepare methylamine or dimethylamine. Dimethylamine is generally prepared in industrial quantities by continuous reaction of methanol (and/or dimethylether) and ammonia in the presence of a silica-alumina catalyst. The reactants are typically combined in the vapor phase, at temperatures in the range of 300°C to 500°C, and at elevated pressures. Such a process is disclosed in U.S. Patent No. 4,737,592, issued April 12, 1988 to Abrams et al.

The catalyst is used in its acid form. Acid forms of molecular sieves can be prepared by a variety of techniques. Desirably, the molecular sieve used to prepare dimethylamine will be in the hydrogen form, or have an alkali or alkaline earth metal, such as Na, K, Rb, or Cs, ioM-exchanged into it.

The process of the present invention involves reacting methanol, dimethylether or a mixture thereof and ammonia in amounts sufficient to provide a carbon/nitrogen (C/N) ratio from about 0.2 to about 1.5, for example about 0.5 to about 1.2. The reaction is conducted at a temperature from about 250°C to about 450°C, for example about 300°C to about 400°C. Reaction pressures can vary from about 7-7000 kPa (1-1000 psi), for example about 70-3000 kPa (10-500 psi). A methanol and/or dimethylether space time of about 0.01-80 hours, for example 0.10-1.5 hours, is typically used. This space time is calculated as the mass of catalyst divided by the mass flow rate of methanol/dimethylether introduced into the reactor.

Treatment of Engine Exhaust (Cold Start Emissions)

Gaseous waste products resulting from the combustion of hydrocarbonaceous fuels, such as gasoline and fuel oils, comprise carbon monoxide, hydrocarbons and nitrogen oxides as products of combustion or incomplete combustion, and pose a serious health problem with respect to pollution of the atmosphere. While exhaust gases from other carbonaceous fuel- burning sources, such as stationary engines, industrial furnaces, etc., contribute substantially to air pollution, the exhaust gases from automotive engines are a principal source of pollution. Because of these health problem concerns, the Environmental Protection Agency (EPA) has promulgated strict controls on the amounts of carbon monoxide, hydrocarbons and nitrogen oxides which automobiles can emit. The implementation of these controls has resulted in the use of catalytic converters to reduce the amount of pollutants emitted from automobiles.

In order to achieve the simultaneous conversion of carbon monoxide, hydrocarbon and nitrogen oxide pollutants, it has become the practice to employ catalysts in conjunction with air-to-fuel ratio control means which functions in response to a feedback signal from an oxygen sensor in the engine exhaust system. Although these three component control catalysts work quite well after they have reached operating temperature of about 300°C, at lower temperatures they are not able to convert substantial amounts of the pollutants. What this means is that when an engine and in particular an automobile engine is started up, the three component control catalyst is not able to convert the hydrocarbons and other pollutants to innocuous compounds.

Adsorbent beds have been used to adsorb the hydrocarbons during the cold start portion of the engine. Although the process typically will be used with hydrocarbon fuels, the instant invention can also be used to treat exhaust streams from alcohol fueled engines. The adsorbent bed is typically placed immediately before the catalyst. Thus, the exhaust stream is first flowed through the adsorbent bed and then through the catalyst. The adsorbent bed preferentially adsorbs hydrocarbons over water under the conditions present in the exhaust stream. After a certain amount of time, the adsorbent bed has reached a temperature (typically about 150°C) at which the bed is no longer able to remove hydrocarbons from the exhaust stream. That is, hydrocarbons are actually desorbed from the adsorbent bed instead of being adsorbed. This regenerates the adsorbent bed so that it can adsorb hydrocarbons during a subsequent cold start.

The prior art reveals several references dealing with the use of adsorbent beds to minimize hydrocarbon emissions during a cold start engine operation. One such reference is U.S. Patent No. 3,699,683, in which an adsorbent bed is placed after both a reducing catalyst and an oxidizing catalyst. The patentees disclose that when the exhaust gas stream is below 200°C the gas stream is flowed through the reducing catalyst then through the oxidizing catalyst and finally through the adsorbent bed, thereby adsorbing hydrocarbons on the adsorbent bed. When the temperature goes above 200°C the gas stream which is discharged from the oxidation catalyst is divided into a major and minor portion, the major portion being discharged directly into the atmosphere and the minor portion passing through the adsorbent bed whereby unburned hydrocarbon is desorbed and then flowing the resulting minor portion of this exhaust stream containing the desorbed unburned hydrocarbons into the engine where they are burned.

Another reference is U.S. Patent No. 2,942,932 which teaches a process for oxidizing carbon monoxide and hydrocarbons which are contained in exhaust gas streams. The process disclosed in this patent consists of flowing an exhaust stream which is below 800° F. into an adsorption zone which adsorbs the carbon monoxide and hydrocarbons and then passing the resultant stream from this adsorption zone into an oxidation zone. When the temperature of the exhaust gas stream reaches about 800°F (426.7°C), the exhaust stream is no longer passed through the adsorption zone but is passed directly to the oxidation zone with the addition of excess air.

U.S. Patent No. 5,078,979, issued January 7, 1992 to Dunne, discloses treating an exhaust gas stream from an engine to prevent cold start emissions using a molecular sieve adsorbent bed. Examples of the molecular sieve include faujasites, clinoptilolites, mordenites, chabazite, silicalite, zeolite Y, ultrastable zeolite Y, and ZSM-5.

Canadian Patent No. 1,205,980 discloses a method of reducing exhaust emissions from an alcohol fueled automotive vehicle. This method consists of directing the cool engine startup exhaust gas through a bed of zeolite particles and then over an oxidation catalyst and then the gas is discharged to the atmosphere. As the exhaust gas stream warms up it is continuously passed over the adsorption bed and then over the oxidation bed.

As stated, this invention generally relates to a process for treating an engine exhaust stream and in particular to a process for minimizing emissions during the cold start operation of an engine. The engine consists of any internal or external combustion engine which generates an exhaust gas stream containing noxious components or pollutants including unburned or thermally degraded hydrocarbons or similar organics. Other noxious components usually present in the exhaust gas include nitrogen oxides and carbon monoxide. The engine may be fueled by a hydrocarbonaceous fuel. As used herein, the term "hydrocarbonaceous fuel" includes hydrocarbons, alcohols and mixtures thereof. Examples of hydrocarbons which can be used to fuel the engine are the mixtures of hydrocarbons which make up gasoline or diesel fuel. The alcohols which may be used to fuel engines include ethanol and methanol. Mixtures of alcohols and mixtures of alcohols and hydrocarbons can also be used. The engine may be a jet engine, gas turbine, internal combustion engine, such as an automobile, truck or bus engine, a diesel engine or the like. The process of this invention is particularly suited for hydrocarbon, alcohol, or hydrocarbon-alcohol mixture, internal combustion engine mounted in an automobile. For convenience the description will use hydrocarbon as the fuel to exemplify the invention. The use of hydrocarbon in the subsequent description is not to be construed as limiting the invention to hydrocarbon fueled engines.

When the engine is started up, it produces a relatively high concentration of hydrocarbons in the engine exhaust gas stream as well as other pollutants. Pollutants will be used herein to collectively refer to any unburned fuel components and combustion byproducts found in the exhaust stream. For example, when the fuel is a hydrocarbon fuel, hydrocarbons, nitrogen oxides, carbon monoxide and other combustion byproducts will be found in the engine exhaust gas stream. The temperature of this engine exhaust stream is relatively cool, generally below 500°C and typically in the range of 200°C to 400°C This engine exhaust stream has the above characteristics during the initial period of engine operation, typically for the first 30 to 120 seconds after startup of a cold engine. The engine exhaust stream will typically contain, by volume, about 500 to 1000 ppm hydrocarbons.

In one embodiment, the engine exhaust gas stream which is to be treated is flowed over a combination of molecular sieves which preferentially adsorbs the hydrocarbons over water to provide a first exhaust stream, and flowing the first exhaust gas stream over a catalyst to convert any residual hydrocarbons and other pollutants contained in the first exhaust gas stream to innocuous products and provide a treated exhaust stream and discharging the treated exhaust stream into the atmosphere. The combination of molecular sieves includes molecular sieve SSZ-81 in combination with:

(1) a small pore crystalline molecular sieve or mixture of molecular sieves having pores no larger than 8 membered rings ("8 MR") selected from the group consisting of SSZ- 13, SSZ-16, SSZ-36, SSZ-39. SSZ-50, SSZ-52 and SSZ-73 and having a mote ratio of at least 10 of (a) an oxide of a first tetravalent element to (b) an oxide of a trivalent element, pentavalent element, second tetravalent element which is different from the first tetravalent element or mixture thereof; and/or

(2) a large pore crystalline molecular sieve having pores at least as large as 10 membered rings (" 10 MR") selected from the group consisting of SSZ-26, SSZ-33, SSZ-64, zeolite Beta, CIT-1, CIT-6 and ITQ-4 and having a mole ratio of at least 10 of (a) an oxide of a first tetravalent element to (b) an oxide of a trivalent element, pentavalent element second tetravalent element which is different from the first tetravaient element or mixture thereof.

The engine exhaust gas stream which is to be treated is flowed over a molecular sieve bed comprising molecular sieve SSZ-81 a first exhaust stream. Molecular sieve SSZ-81 is described herein. The first exhaust stream which is discharged from the molecular sieve bed is now flowed over a catalyst to convert the pollutants contained in the first exhaust stream to innocuous components and provide a treated exhaust stream which is discharged into the atmosphere. It is understood that prior to discharge into the atmosphere, the treated exhaust stream may be flowed through a muffler or other sound reduction apparatus well known in the art.

The catalyst which is used to convert the pollutants to innocuous components is usually referred to in the art as a three-component control catalyst because it can

simultaneously oxidize any residual hydrocarbons present in the first exhaust stream to carbon dioxide and water, oxidize any residual carbon monoxide to carbon dioxide and reduce any residual nitric oxide to nitrogen and oxygen. In some cases the catalyst may not be required to convert nitric oxide to nitrogen and oxygen, e.g., when an alcohol is used as the fuel. In this case the catalyst is called an oxidation catalyst. Because of the relatively low temperature of the engine exhaust stream and the first exhaust stream, this catalyst does not function at a very high efficiency, thereby necessitating the molecular sieve bed.

When the molecular sieve bed reaches a sufficient temperature, typically about 150- 200°C, the pollutants which are adsorbed in the bed begin to desorb and are carried by the first exhaust stream over the catalyst. At this point the catalyst has reached its operating temperature and is therefore capable of fully converting the pollutants to innocuous components.

The adsorbent bed used in the instant invention can be conveniently employed in particulate form or the adsorbent can be deposited onto a solid monolithic carrier. When particulate form is desired, the adsorbent can be formed into shapes such as pills, pellets, granules, rings, spheres, etc. In the employment of a monolithic form, it is usually most convenient to employ the adsorbent as a thin film or coating deposited on an inert carrier material which provides the structural support for the adsorbent. The inert carrier material can be any refractory material such as ceramic or metallic materials. It is desirable that the carrier material be unreactive with the adsorbent and not be degraded by the gas to which it is exposed. Examples of suitable ceramic materials include sillimanite, petalite, cordierite, mullite, zircon, zircon mullite, spondumene, alumina-titanate, etc. Additionally, metallic materials which are within the scope of this invention include metals and alloys as disclosed in U.S. Patent No. 3,920,583 which are oxidation resistant and are otherwise capable of withstanding high temperatures.

The carrier material can best be utilized in any rigid unitary configuration which provides a plurality of pores or channels extending in the direction of gas flow. The configuration may be a honeycomb configuration. The honeycomb structure can be used advantageously in either unitary form, or as an arrangement of multiple modules. The honeycomb structure is usually oriented such that gas flow is generally in the same direction as the cells or channels of the honeycomb structure. For a more detailed discussion of monolithic structures, refer to U.S. Patent Nos. 3,785,998 and 3,767,453.

The molecular sieve is deposited onto the carrier by any convenient way well known in the art. A desirable method involves preparing a slurry using the molecular sieve and coating the monolithic honeycomb carrier with the slurry. The slurry can be prepared by means known in the art such as combining the appropriate amount of the molecular sieve and a binder with water. This mixture is then blended by using means such as sonification, milling, etc. This slurry is used to coat a monolithic honeycomb by dipping the honeycomb into the slurry, removing the excess slurry by draining or blowing out the channels, and heating to about 100°C. If the desired loading of molecular sieve is not achieved, the above process may be repeated as many times as required to achieve the desired loading.

Instead of depositing the molecular sieve onto a monolithic honeycomb structure, one can take the molecular sieve and form it into a monolithic honeycomb structure by means known in the art.

The adsorbent may optionally contain one or more catalytic metals dispersed thereon. The metals which can be dispersed on the adsorbent are the noble metals which consist of platinum, palladium, rhodium, ruthenium, and mixtures thereof. The desired noble metal may be deposited onto the adsorbent, which acts as a support, in any suitable manner well known in the art. One example of a method of dispersing the noble metal onto the adsorbent support involves impregnating the adsorbent support with an aqueous solution of a decomposable compound of the desired noble metal or metals, drying the adsorbent which has the noble metal compound dispersed on it and then calcining in air at a temperature of about 400° to about 500°C for a time of about 1 to about 4 hours. By decomposable compound is meant a compound which upon heating in air gives the metal or metal oxide. Examples of the decomposable compounds which can be used are set forth in U.S. Patent No. 4,791,091 which is incorporated by reference. Examples of decomposable compounds are chloroplatinic acid, rhodium trichloride, chloropalladic acid, hexachloroiridate (IV) acid and

hexachlororuthenate. It is typical that the noble metal be present in an amount ranging from about 0.01 to about 4 weight percent of the adsorbent support. Specifically, in the case of platinum and palladium the range is 0.1 to 4 weight percent, while in the case of rhodium and ruthenium the range is from about 0.01 to 2 weight percent.

These catalytic metals are capable of oxidizing the hydrocarbon and carbon monoxide and reducing the nitric oxide components to innocuous products. Accordingly, the adsorbent bed can act both as an adsorbent and as a catalyst.

The catalyst which is used in this invention is selected from any three component control or oxidation catalyst well known in the art. Examples of catalysts are those described in U.S. Patent Nos. 4,528,279; 4,791,091; 4,760,044; 4,868, 148; and 4,868, 149, which are all incorporated by reference. Desirable catalysts well known in the art are those that contain platinum and rhodium and optionally palladium, while oxidation catalysts usually do not contain rhodium. Oxidation catalysts usually contain platinum and/or palladium metal. These catalysts may also contain promoters and stabilizers such as barium, cerium, lanthanum, nickel, and iron. The noble metals promoters and stabilizers are usually deposited on a support such as alumina, silica, titania, zirconia, alumino silicates, and mixtures thereof with alumina being desirable. The catalyst can be conveniently employed in particulate form or the catalytic composite can be deposited on a solid monolithic carrier with a monolithic carrier being desirable. The particulate form and monolithic form of the catalyst are prepared as described for the adsorbent above.

The molecular sieve used in the adsorbent bed is SSZ-81.

Beckmann Rearrangement

The present invention relates to a process for the preparation of amides from oximes. The present invention further relates to the use of SSZ-81 in the catalytic transformation of oximes, such as cyclohexanone oxime, to amides, such as epsilon-caprolactam (caprolactam), also known as Beckmann catalytic rearrangement. The Beckmann rearrangement is shown below (where sulfuric acid is used instead of a molecular sieve catalyst).

O

H₂S0₄

1SL _^ R'

HO ^* NN R'

H

R

Amides, and in particular caprolactam, are known in literature as important intermediates for chemical syntheses and as raw materials for the preparation of polyamide resins.

Caprolactam is produced industrially by cyclohexanone oxime rearrangement in liquid phase using sulfuric acid or oleum. The rearranged product is neutralized with ammonia causing the joint formation of ammonium sulfate. This technology has numerous problems linked to the use of sulfuric acid, to the formation of high quantities of ammonium sulfate, with relative problems of disposal, corrosion of the equipment owing to the presence of acid vapors, etc. Alternative processes have been proposed in the literature for the catalytic rearrangement of cyclohexanone oxime into caprolactam, in which solids of an acid nature are used, as catalysts, selected from derivatives of boric acid, zeolites, now-zeolitic molecular sieves, solid phosphoric acid, mixed metal oxides, etc.

In particular, European patent 234.088 describes a method for preparing caprolactam which comprises putting cyclohexanone oxime in gaseous state in contact with alumino- silicates of the zeolitic type such as ZSM-5, ZSM-11 or ZSM-23 having a "Constraint Index" of between 1 and 12, an atomic ratio Si/Al of at least 500 (S1O2/AI2O₃ mole ratio of at least 1,000) and an external acid functionality of less than 5 micro equivalents/g.

Zeolites, as described in "Zeolite Molecular Sieves" D. W. Breck, John Wiley &

Sons, (1974) or in "Nature" 381 (1996), 295, are crystalline products characterized by the presence of a regular microporosity, with channels having dimensions of between 3 and 10 Angstroms. In some particular zeolitic structures there can be cavities with greater dimensions, of up to about 13 Angstroms.

With the aim of providing another method for the preparation of amides, and in particular of caprolactam, a new process has now been found which uses a catalyst containing SSZ-81. The present invention therefore relates to a process for the preparation of amides via the catalytic rearrangement of oximes which comprises putting an oxime in vapor phase in contact with a catalyst comprising molecular sieve SSZ-81.

Other methods for converting oximes to amides via Beckmann rearrangement are disclosed in U.S. Patent No. 4,883,915, issued November 28, 1989 to McMahon, which uses a crystalline borosilicate molecular sieve in the catalyst and U.S. Patent No. 5,942,613, issued August 24, 1999 to Carati et al, which uses a mesoporous silica-alumina in the catalyst.

A desirable amide is epsilon-caprolactam (caprolactam) and the desirable oxime is cyclohexanone oxime (CEOX). In particular, the catalytic rearrangement of the

cyclohexanone oxime takes place at a pressure of between 0.05 and 10 bars and at a temperature of between 250°C and 500°C, for example between 300°C and 450°C. More specifically, the cyclohexanone oxime, in vapor phase, is fed to the reactor containing the catalyst in the presence of a solvent and optionally an incondensable gas. The cyclohexanone oxime is dissolved in the solvent and the mixture thus obtained is then vaporized and fed to the reactor. The solvent should be essentially inert to the oxime and the amide, as well as the catalyst. Useful solvents include, but are not limited to, lower boiling hydrocarbons, alcohols and ethers.

Desirable solvents are of the type R¹ - O - R² wherein R¹ is a Ci - C₄ alkyl chain and R² can be a hydrogen atom or an alkyl chain containing a number of carbon atoms less than or equal to R¹. These solvents can be used alone or mixed with each other or combined with an aromatic hydrocarbon such as benzene or toluene. Alcohols with a Ci - C₂ alkyl chain are particularly desirable.

The cyclohexanone oxime is fed to the rearrangement reactor with a weight ratio with respect to the catalyst which is such as to give a WHSV (Weight Hourly Space Velocity), expressed as Kg of cyclohexanone oxime/kg of catalyst/time, of between 0.1 and 50 hr. ¹, for example between 0.5 and 20 hr.^"1.

The deterioration of the catalyst is due to the formation of organic residues which obstruct the pores of the catalyst and poison its active sites. The deterioration process is slow and depends on the operating conditions and in particular the space velocity, solvent, temperature, composition of the feeding. The catalytic activity however can be efficiently reintegrated by the combustion of the residues, by treatment in a stream of air and nitrogen at a temperature of between 450°C and 600°C.

EXAMPLES

The following examples demonstrate but do not limit the present invention.

EXAMPLE 1

Synthesis of SSZ-81 Using l ,5-bis(l-azonia-bicvclor2.2.2^"|octane)pentane Dication 5.0 g of a hydroxide solution of l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane ([OH ]

= 0.4 mmol/g) was added to a Teflon container. Next, 0.18 g of zeolite Y-52 (as provided by Union Carbide Corp.), 1.50 g of a IN NaOH solution and 0.50 g of water was added to the container. Finally, 0.50 g CAB-O-SIL M-5 fumed silica (Cabot Corporation) was slowly added and the gel was thoroughly mixed. The Teflon liner was then capped and sealed within a steel Parr autoclave. The autoclave was placed on a spit within a convection oven at 160°C. The autoclave was tumbled at 43 rpm over the course of 17 days in the heated oven. The autoclave was then removed and allowed to cool to room temperature. The solids were then recovered by filtration and washed thoroughly with deionized water. The solids were allowed to dry at room temperature.

The resulting product was analyzed by powder XRD. Figure 1 shows the powder XRD pattern of the product of this Example. Table 6 below shows the powder X-ray diffraction lines for the resulting product.

TABLE 6

2 Theta^(a) d-spacing (Angstroms) Relative Intensity (%)

6.14 14.38 8.1

7.02 12.58 2.2

7.41 1 1.91 27.0

low-intensity,

41 peak - 10.50^(b)

broad band low-intensity,

;.50 - 22.03 peak^(c)

broad band

11.08 7.98 3.3

12.86 6.88 2.9

15.57 5.69 4.1

18.72 4.74 4.9

22.03 4.03 21.4

22.58 3.94 100.00

23.30 3.81 13.8

24.12 3.69 14.2

25.10 3.55 6.3

26.12 3.41 3.9

26.36 3.38 4.4

27.30 3.26 7.8

28.55 3.12 8.6

31.29 2.86 5.0

33.94 2.64 1.8

34.08 2.63 2.6

36.69 2.45 3.4

' ± 0.20

'' ^(c> In the pattern for as-synthesized SSZ-81, it can be seen that there is a first low- intensity (W), broad-band running from the peak near 2Θ = 7.4 degrees down to baseline at near 2Θ = 10.5 degrees, and a second low-intensity, broad-band rising from the baseline at about 2Θ = 18.5 degrees and then merging into a well-defined peak just beyond 22 degrees. This behavior is seen in all samples of as-synthesized SSZ-81. EXAMPLE 2

Calcination of SSZ-81

The product of Example 1 was calcined inside a muffle furnace under a flow of 2%oxygen/98%nitrogen heated to 595°C at a rate of l°C/min and held at 595°C for five hours, cooled and then analyzed by powder XRD. The resulting XRD pattern is shown in Figure 2. Table 7 below shows the powder XRD lines for the calcined molecular sieve product.

TABLE 7

2 Theta^(a) d-spacing (Angstroms) Relative Intensity (%)

7.45 1 1.86 89.1

low-intensity,

7.45 peak - 10.50^(b)

broad band

9.85 8.97 7.5

1 1.62 7.61 6.7

14.38 6.15 7.3

low-intensity,

18.50 - 22.26 peak^(c)

broad band

22.26 3.99 15.5

22.79 3.90 100.00

23.53 3.78 21.9

24.36 3.65 19.4

25.37 3.51 7.6

26.37 3.38 13.3

26.69 3.34 5.5

27.53 3.24 10.4

28.67 3.1 1 6.1

^(a) ± 0.20

'' ^(c> In the pattern for calcined SSZ-81, it can be seen that there is a first low- intensity (W), broad-band running from the peak near 2Θ = 7.4 degrees down to baseline at near 2Θ = 10.5 degrees, and a second low-intensity, broad-band rising from the baseline at about 2Θ = 18.5 degrees and then merging into a well-defined peak just beyond 22 degrees. This behavior is seen in all samples of calcined SSZ-81.

The XRD pattern indicates that the material remains stable after calcination to remove the organic SDA.

EXAMPLE 3

H ⁺ Exchange

Ion-exchange of calcined SSZ-81 material (prepared in Example 2) is performed using NH₄NO₃ to convert the molecular sieve from its Na⁺ form to the NH₄ ⁺ form, and, ultimately, the H⁺ form. Typically, the same mass of NH₄NO₃ as the molecular sieve is slurried in water at a ratio of 25-50: 1 water to zeolite. The exchange solution is heated at 95°C for 2 hours and then filtered. This procedure can be repeated up to three times.

Following the final exchange, the molecular sieve is washed several times with water and dried. This NH₄ ⁺ form of SSZ-81 can then be converted to the H form by calcination (as described in Example 2) to 540°C.

EXAMPLE 4

Constraint Index

0.5 grams of calcined H⁺ form material prepared per Example 3, in a 20-40 pelletized and meshed range, was loaded into a stainless steel reactor (glass wool packing on both sides of the catalyst bed ) and run in a Constraint Index test (50% n-hexane/50% 3-methylpentane (3 -MP)). A normal feed rate was used (8 μΐ/min.) and a first test was run at 260°C (500°F) and a second test was run at 316°C (600°F). Each test was run after the catalyst had been dried in the reactor to near 538°C (1000°F). Helium flow was used. (See, Zones and Harris, Microporous and Mesoporous Materials 35-36 (2000), pp. 31-46.)

As shown in Tables 8 and 9, at 10 minutes on-stream, -92% of the feed was being converted with approximately equal amounts of each reactant in the first test, and in the second test over 99% of the feed was being converted with about equal amounts of each reactant. TABLE 8

n-Ce conversion (%) 89.7

3-methylpentane conversion (%) 95.1

Feed conversion (%) 92.4

Constraint Index (including 2-MP) 1.05

Constraint Index (excluding ; 2-MP) 0.75

MP = methylpentane

TABLE 9

η-Ce conversion (%) 99.3

3-MP (%) 99.2

Feed conversion (%) 99.3

Constraint Index (including 2-MP) 1.21

Constraint Index (excluding ; 2-MP) 1.03

MP = methylpentane

EXAMPLE 5

Adsorption of 2,2-Dimethylbutane

The calcined material of Example 3 was then tested for the uptake of the hydrocarbon 2,2-dimethylbutane. This adsorbate does not enter small pore zeolites (8-ring portals) and sometimes is hindered in entering intermediate pore zeolites like ZSM-5. The SSZ-81 showed a profile characteristic of a multi-dimensional, large-pore material (such as Y zeolite), showing rapid uptake and high pore filling.

At P/Po of -0.3 and at room temperature, SSZ-81 was shown to adsorb over 0.18 cc/gram after 15 minutes of exposure to the 2,2-dimethylbutane adsorbate, and about 0.19 cc/gram after about 1 hour of exposure to the adsorbate.

EXAMPLE 6

Synthesis of SSZ-81 Using a Combination of Dications 1.25 g of a hydroxide solution of l,5-bis(l-azonia-bicyclo[2.2.2]octane)pentane ([OH

] = 0.40 mmol/g) and 3.75 g of a hydroxide solution of l,5-bis(l,4- diazabicyclo[2.2.2]octane)pentane ([OFF] = 0.41 mmol/g) were added to a Teflon container. Next, 0.18 g of zeolite Y-52 (provided by Union Carbide Corporation), 1.50 g of a IN NaOH solution and 0.50 g of water were added to the container. Finally, 0.50 g CAB-O-SIL M-5 fumed silica (Cabot Corporation) was slowly added and the gel was thoroughly mixed. The Teflon liner was then capped and sealed within a steel Parr autoclave. The autoclave was placed on a spit within a convection oven at 160°C. The autoclave was tumbled at 43 rpm over the course of four weeks in the heated oven. The autoclave was then removed and allowed to cool to room temperature. The solids were then recovered by filtration and washed thoroughly with deionized water. The solids were allowed to dry at room temperature.

The resulting product was analyzed by powder XRD. The XRD analysis indicated the product was SSZ-81.

EXAMPLE 7

Synthesis of SSZ-81 Using a 1.5-bis(1.4-diazabicvclor2.2.21octane)pentane Dication 5.0 g of a hydroxide solution of l,5-bis(l,4-diazabicyclo[2.2.2]octane)pentane ([OFF]

= 0.41 mmol/g) was added to a Teflon container. Next, 0.18 g of zeolite Y-52 (provided by Union Carbide Corp), 1.50 g of a IN NaOH solution and 0.50 g of water were added to the container. Finally, 0.50 g CAB-O-SIL M-5 fumed silica (Cabot Corporation) was slowly added and the gel was thoroughly mixed. The Teflon liner was then capped and sealed within a steel Parr autoclave. The autoclave was placed on a spit within a convection oven at 160°C. The autoclave was tumbled at 43 rpm over the course of six weeks in the heated oven, with periodic interruption to look for product formation. The autoclave was then removed after 6 weeks and allowed to cool to room temperature. The solids were then recovered by filtration and washed thoroughly with deionized water. The solids were allowed to dry at room temperature.

The resulting product was analyzed by powder XRD. The XRD analysis indicated the product was a mixture of SSZ-81 and some remaining unreacted zeolite Y-52.

EXAMPLE 8

Preparation of Hydroisomerization Catalyst

Al-SSZ-81 in H⁺-form prepared in accordance with the procedure outlined in Example 3 herein, was ion-exchanged with an aqueous (NH₃)₄Pd(N0₃)2 solution at pH of -10.3 to load the zeolite with 0.5 wt% Pd. The Pd/Al-SSZ-81 molecular sieve was then calcined in air at 450°F (232°C) for 5 hours, and subsequently reduced in hydrogen prior to the catalytic experiment set forth in Example 9.

EXAMPLE 9

n-Hexane Hydroisomerization over Pd/Al-SSZ-81

The catalytic reaction of hydroisomerization of n-hexane was carried out using the Pd/ SSZ-81 catalyst prepared in Example 8 herein, in a flow-type fixed bed reactor with pure n- hexane as the feed. The hydroisomerization conditions included a pressure of 200 pounds per square inch gauge (psig)(1.38MPa), a liquid hour space velocity (LHSV) of 1 h^"1, and a H₂ to hydrocarbon molar ratio of 6: 1. The reaction temperatures ranged from 400 to 620°F (204- 327°C) in 10°F (5.5°C) increments. The reaction products were analyzed with an on-line gas chromatograph to quantify all the cracking and isomerization products. Representative results are shown in Table 10.

TABLE 10

Claims

WHAT IS CLAIMED IS:

1. A process for converting hydrocarbons comprising contacting a hydrocarbonaceous feed at hydrocarbon converting conditions with a catalyst comprising a molecular sieve having a mole ratio greater than about 10 of silicon oxide to aluminum oxide and having, after calcination, an X-ray diffraction pattern substantially as shown in the following Table:

2 Theta d-spacing Relative Absolute

(Angstroms) Intensity (%)

7.45 ± 0.20 1 1.86 S

7.45 peak - 10.50, ± 0.20 W, broad band

14.38 6.15 W

18.50 - 22.26 peak, ± 0.20 W, broad band

22.26 ± 0.20 3.99 W

22.79 ± 0.20 3.90 S

23.53 ± 0.20 3.78 W-M

24.36 ± 0.20 3.65 W-M

25.37 ± 0.20 3.51 W

26.37 ± 0.20 3.38 W

27.53 ± 0.20 3.24 W

28.67 ± 0.20 3.11 W

54

2. The process of Claim 1, wherein the molecular sieve is prepared from a reaction mixture comprising, in terms of mole ratios, a composition as described in the following Table:

Si0₂ / A1₂0₃ 20 - 80

(Q + A) / Si0₂ 0.05 - 0.30

OH7 Si0₂ 0.20 - 0.60

H₂0 / Si0₂ 10 - 50

wherein:

3. The process of Claim 1, wherein the molecular sieve has a composition, as- synthesized and in the anhydrous state, in terms of mole ratios, as follows:

Si0₂/ Al₂0₃ 10 - 60

(Q + A) / Si0₂ 0.02 - 0.10

M / Si0₂ 0.01 - 1.0

4. The process of Claim 1, wherein the molecular sieve has a composition, as- synthesized and in the anhydrous state, in terms of mole ratios, as follows:

Si0₂/ Al₂0₃ 20 - 35

(Q + A) / Si0₂ 0.04 - 0.07

M / Si0₂ 0.02 - 0.04

55

5. The process of Claim 1, wherein the process is a process selected from the group consisting of hydrocracking, dewaxing, catalytic cracking, aromatics formation,

isomerization, alkylation and transalkylation, conversion of paraffins to aromatics, isomerization of olefins, xylene isomerization, oligomerization, condensation of alcohols, methane upgrading and polymerization of 1 -olefins.

6. The process of Claim 5, wherein the process is a dewaxing process comprising contacting the catalyst with a hydrocarbon feedstock under dewaxing conditions.

7. The process of Claim 1, wherein the process is a process for producing a C2₀+ lube oil from a C2₀+ olefin feed comprising isomerizing said olefin feed under isomerization conditions over the catalyst.

56

8. A process for treating a cold-start engine exhaust gas stream containing hydrocarbons and other pollutants consisting of flowing said engine exhaust gas stream over a molecular sieve bed which preferentially adsorbs the hydrocarbons over water to provide a first exhaust stream, and flowing the first exhaust gas stream over a catalyst to convert any residual hydrocarbons and other pollutants contained in the first exhaust gas stream to innocuous products and provide a treated exhaust stream and discharging the treated exhaust stream into the atmosphere, the molecular sieve bed comprising a molecular sieve having a mole ratio greater than about 10 of silicon oxide to aluminum oxide and having, after calcination, an X- ray diffraction pattern substantially as shown in the following Table:

2 Theta d-spacing Relative Absolute

(Angstroms) Intensity (%)

7.45 ± 0.20 1 1.86 S

7.45 peak - 10.50, ± 0.20 W, broad band

14.38 6.15 W

18.50 - 22.26 peak, ± 0.20 W, broad band

22.26 ± 0.20 3.99 W

22.79 ± 0.20 3.90 S

23.53 ± 0.20 3.78 W-M

24.36 ± 0.20 3.65 W-M

25.37 ± 0.20 3.51 W

26.37 ± 0.20 3.38 W

27.53 ± 0.20 3.24 W

28.67 ± 0.20 3.11 W

57

9. A process for producing methylamine or dimethylamine comprising reacting methanol, dimethyl ether or a mixture thereof and ammonia in the gaseous phase in the presence of a catalyst comprising a molecular sieve having a mole ratio greater than about 10 of silicon oxide to aluminum oxide and having, after calcination, an X-ray diffraction pattern substantially as shown in the following Table:

2 Theta d-spacing Relative Absolute

(Angstroms) Intensity (%)

7.45 ± 0.20 1 1.86 S

7.45 peak - 10.50, ± 0.20 W, broad band

14.38 6.15 W

18.50 - 22.26 peak, ± 0.20 W, broad band

22.26 ± 0.20 3.99 W

22.79 ± 0.20 3.90 S

23.53 ± 0.20 3.78 W-M

24.36 ± 0.20 3.65 W-M

25.37 ± 0.20 3.51 W

26.37 ± 0.20 3.38 W

27.53 ± 0.20 3.24 W

28.67 ± 0.20 3.11 W

58

10. A process for separating gasses using a membrane containing a molecular sieve, the improvement comprising using as the molecular sieve a molecular sieve having a mole ratio greater than about 10 of silicon oxide to aluminum oxide and having, after calcination, an X- ray diffraction pattern substantially as shown in the following Table:

2 Theta d-spacing Relative Absolute

(Angstroms) Intensity (%)

7.45 ± 0.20 1 1.86 S

7.45 peak - 10.50, ± 0.20 W, broad band

14.38 6.15 W

18.50 - 22.26 peak, ± 0.20 W, broad band

22.26 ± 0.20 3.99 W

22.79 ± 0.20 3.90 S

23.53 ± 0.20 3.78 W-M

24.36 ± 0.20 3.65 W-M

25.37 ± 0.20 3.51 W

26.37 ± 0.20 3.38 W

27.53 ± 0.20 3.24 W

28.67 ± 0.20 3.11 W

59

11. A process for the production of light olefins from a feedstock comprising an oxygenate or mixture of oxygenates, the process comprising reacting the feedstock at effective conditions over a catalyst comprising a molecular sieve having a mole ratio greater than about 10 of silicon oxide to aluminum oxide and having, after calcination, an X-ray diffraction pattern substantially as shown in the following Table:

2 Theta d-spacing Relative Absolute

(Angstroms) Intensity (%)

7.45 ± 0.20 1 1.86 S

7.45 peak - 10.50, ± 0.20 W, broad band

14.38 6.15 W

18.50 - 22.26 peak, ± 0.20 W, broad band

22.26 ± 0.20 3.99 W

22.79 ± 0.20 3.90 S

23.53 ± 0.20 3.78 W-M

24.36 ± 0.20 3.65 W-M

25.37 ± 0.20 3.51 W

26.37 ± 0.20 3.38 W

27.53 ± 0.20 3.24 W

28.67 ± 0.20 3.11 W

60 A process for the reduction of oxides of nitrogen contained in a gas stream wherein process comprises contacting the gas stream with a molecular sieve having a mole ratio ter than about 10 of silicon oxide to aluminum oxide and having, after calcination, an X- diffraction pattern substantially as shown in the following Table:

2 Theta d-spacing Relative Absolute

(Angstroms) Intensity (%)

7.45 ± 0.20 1 1.86 S

7.45 peak - 10.50, ± 0.20 W, broad band

14.38 6.15 W

18.50 - 22.26 peak, ± 0.20 W, broad band

22.26 ± 0.20 3.99 W

22.79 ± 0.20 3.90 S

23.53 ± 0.20 3.78 W-M

24.36 ± 0.20 3.65 W-M

25.37 ± 0.20 3.51 W

26.37 ± 0.20 3.38 W

27.53 ± 0.20 3.24 W

28.67 ± 0.20 3.11 W

61