WO1997017291A1 - Alumina source for non-zeolitic molecular sieves - Google Patents

Alumina source for non-zeolitic molecular sieves Download PDF

Info

Publication number
WO1997017291A1
WO1997017291A1 PCT/US1996/017714 US9617714W WO9717291A1 WO 1997017291 A1 WO1997017291 A1 WO 1997017291A1 US 9617714 W US9617714 W US 9617714W WO 9717291 A1 WO9717291 A1 WO 9717291A1
Authority
WO
WIPO (PCT)
Prior art keywords
molecular sieve
reaction mixture
ofthe
less
alumina
Prior art date
Application number
PCT/US1996/017714
Other languages
French (fr)
Inventor
Stephen J. Miller
Original Assignee
Chevron U.S.A. Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=27070285&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=WO1997017291(A1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Priority claimed from US08/704,055 external-priority patent/US5741751A/en
Application filed by Chevron U.S.A. Inc. filed Critical Chevron U.S.A. Inc.
Priority to AU75539/96A priority Critical patent/AU7553996A/en
Priority to KR1019980703491A priority patent/KR19990067476A/en
Priority to EP96937904A priority patent/EP0859743B2/en
Priority to JP51827097A priority patent/JP4313436B2/en
Priority to DE69604414T priority patent/DE69604414T3/en
Publication of WO1997017291A1 publication Critical patent/WO1997017291A1/en

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B37/00Compounds having molecular sieve properties but not having base-exchange properties
    • C01B37/06Aluminophosphates containing other elements, e.g. metals, boron
    • C01B37/08Silicoaluminophosphates (SAPO compounds), e.g. CoSAPO
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J29/00Catalysts comprising molecular sieves
    • B01J29/82Phosphates
    • B01J29/84Aluminophosphates containing other elements, e.g. metals, boron
    • B01J29/85Silicoaluminophosphates (SAPO compounds)
    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B37/00Compounds having molecular sieve properties but not having base-exchange properties
    • C01B37/04Aluminophosphates (APO compounds)
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G11/00Catalytic cracking, in the absence of hydrogen, of hydrocarbon oils
    • C10G11/02Catalytic cracking, in the absence of hydrogen, of hydrocarbon oils characterised by the catalyst used
    • C10G11/04Oxides
    • C10G11/05Crystalline alumino-silicates, e.g. molecular sieves
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G45/00Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds
    • C10G45/58Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to change the structural skeleton of some of the hydrocarbon content without cracking the other hydrocarbons present, e.g. lowering pour point; Selective hydrocracking of normal paraffins
    • C10G45/60Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to change the structural skeleton of some of the hydrocarbon content without cracking the other hydrocarbons present, e.g. lowering pour point; Selective hydrocracking of normal paraffins characterised by the catalyst used
    • C10G45/64Refining of hydrocarbon oils using hydrogen or hydrogen-generating compounds to change the structural skeleton of some of the hydrocarbon content without cracking the other hydrocarbons present, e.g. lowering pour point; Selective hydrocracking of normal paraffins characterised by the catalyst used containing crystalline alumino-silicates, e.g. molecular sieves
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10GCRACKING HYDROCARBON OILS; PRODUCTION OF LIQUID HYDROCARBON MIXTURES, e.g. BY DESTRUCTIVE HYDROGENATION, OLIGOMERISATION, POLYMERISATION; RECOVERY OF HYDROCARBON OILS FROM OIL-SHALE, OIL-SAND, OR GASES; REFINING MIXTURES MAINLY CONSISTING OF HYDROCARBONS; REFORMING OF NAPHTHA; MINERAL WAXES
    • C10G47/00Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions
    • C10G47/02Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions characterised by the catalyst used
    • C10G47/10Cracking of hydrocarbon oils, in the presence of hydrogen or hydrogen- generating compounds, to obtain lower boiling fractions characterised by the catalyst used with catalysts deposited on a carrier
    • C10G47/12Inorganic carriers
    • C10G47/16Crystalline alumino-silicate carriers

Definitions

  • This invention relates to the synthesis of non-zeolitic molecular sieves. It more particularly relates to a method of preparing non-zeolitic molecular sieves (NZMS) at low cost and with simplified processing.
  • NZMS non-zeolitic molecular sieves
  • the non-zeolitic molecular sieves to which the present invention is directed comprise crystalline, three-dimensional microporous framework structures of tetrahedrally-bound AlO 2 and PO 2 oxide units, and optionally one or more metals in tetrahedral coordination with oxygen atoms. See U.S. Patent No. 4,861,743.
  • the crystalline aluminophosphate-type materials which are prepared by the present process are useful, inter alia, for a number of catalytic conversion processes, including dewaxing, isomerization, hydroisomerization, hydrocracking, hydrogenation.
  • a non-zeolitic molecular sieve is prepared from a reaction mixture comprising active sources ofthe molecular sieve, including active source(s) of aluminum and phosphorous.
  • active sources of the molecular sieve including active source(s) of aluminum and phosphorous.
  • a preferred active source of alumina in the conventional preparation ofthe non-zeolitic molecular sieves is an aluminum alkoxide, such as aluminum isopropoxide, or a pseudo-boehmite hydrated aluminum oxide.
  • U.S. Patent No. 4,310,440 which discloses aluminum phosphate molecular sieves
  • U.S. Patent No. 4,440,871 which discloses silicoaluminophosphates and their preparation, list these sources of aluminum for the preparation of these molecular sieves.
  • non-zeolitic molecular sieves having catalytic properties such as catalyst activity and selectivity in the conversion of petroleum and organic feedstocks, equal to that of a non- zeolitic molecular sieve prepared using an aluminum alkoxide as the alumina source.
  • aluminum alkoxides are expensive relative to other alumina sources.
  • NZMS non-zeolitic molecular sieve
  • the present invention is based in part on the surprising discovery that an improved non-zeolitic molecular sieve having good catalytic activity and selectivity may be prepared using a low cost hydrated alumina source, preferably a particulate hydrated alumina having a small particle size, a low particle density, and a low alkali content.
  • a low cost hydrated alumina source preferably a particulate hydrated alumina having a small particle size, a low particle density, and a low alkali content.
  • the particle size ofthe preferred hydrated alumina source is smaller than that previously taught for the preparation of non-zeolitic molecular sieves, and the alkali content (including sodium) of the preferred particulate alumina is lower than that normally found in low-cost alumina sources.
  • a non-zeolitic molecular sieve having an alkali content within the present range has comparable catalytic performance to a non- zeolitic molecular sieve prepared with an expensive alumina source which is substantially free of alkali.
  • the present invention is directed to a process, and the produced product, for preparing a molecular sieve comprising maintaining a reaction mixture containing an active source of phosphorous and a particulate hydrated alumina under crystallization conditions until crystals ofthe molecular sieve form, the particulate hydrated alumina having an average particle size of less than about 40 ⁇ , a particle density of less than about 1.0 g/cm 3 and an alkali content of less than about 0.12% by weight.
  • the particulate hydrated alumina for this process preferably has an average particle size of less than about 25 ⁇ and more preferably less than about lO ⁇ , with preferably less than about 25% ofthe particulates having an average particle size outside of a range of about O.l ⁇ to about 40 ⁇ .
  • the most preferred particulate hydrated alumina has an average particle size within a range of about 0. l ⁇ to about lO ⁇ , with less than 25% and preferably less than 10% ofthe particles having an average particle size outside of a range of about 0. l ⁇ to about 25 ⁇ .
  • a preferred particulate hydrated alumina for this process has a particle density of less than about 0.9 g/cm 3 , more preferably less than about
  • the present invention is directed to a molecular sieve prepared using a process comprising maintaining a reaction mixture containing an active source of phosphorous and a particulate hydrated alumina under crystallization conditions until crystals ofthe molecular sieve form, the particulate hydrated alumina having an average particle size of less than about 40 ⁇ , a particle density of less than about 1.0 g/cm 3 and an sodium content of less than 0.12 wt%.
  • the present invention is directed to a non-zeolitic molecular sieve which contains less than 500 ppm, preferably from about 75 to about 500 ppm alkali, more preferably from about 75 to about 400 ppm alkali and most preferably from about 75 to about 225 ppm alkali.
  • the present process for preparing crystalline materials containing oxides of aluminum and phosphorous in tetrahedral coordination is characterized in part by the use of a source of alumina which is both cheaper and easier to use than the conventional sources, while producing non-zeolitic molecular sieves having catalytic properties which approach, are equal to or exceed the properties ofthe best non-zeolitic molecular sieves prepared using conventional sources.
  • the particulate hydrated alumina used in the present process for preparing a non- zeolitic molecular sieve has a particle density of less than about 1.0 g/cm 3 , preferably less than about 0.9 g/cm 3 , more preferably less than about 0.8 g/cm 3 and most preferably in the range of about 0.1 g cm 3 to about 0.8 g/cm 3 .
  • the low density particulate alumina includes hydrated aluminas having an H 2 O/AI2O3 molar ratio of Al2 ⁇ 3:nH 2 O, where n is greater than 2.2, preferably greater than 2.6, more preferably greater than 2.8.
  • An example hydrated alumina useful in the present process is Reheis (Berkeley Heights, N.J.) F-2000 aluminum hydroxy carbonate, containing up to 10% carbonate and having an Al 2 O 3 :H 2 O molar ratio corresponding approximately to Al(OH) 3 , or Al 2 O 3 .3H 2 O.
  • the particulate hydrated alumina, as added to the reaction mixture in which the non-zeolitic molecular sieve is formed further has an average particle size of less than about 40 ⁇ , preferably less than about 25 ⁇ , more preferably less than about 15 ⁇ , still more preferably less than about lO ⁇ , and most preferably within the range of about 0.
  • represents a measure of length in microns or, in the alternative, micrometers. In terms of particle size ofthe small particles described herein, this measure of length is a measure ofthe nominal or average diameters ofthe particles, assuming that they approximate a spherical shape, or, in the case of elongated particles have a circular cross-section.
  • a variety of analytical methods are available to practitioners for determining the size of small particles.
  • One such method employs a Coulter Counter, which uses a current generated by platinum electrodes on two sides of an aperture to count the number, and determine the size, of individual particles passing through the aperture.
  • the Coulter Counter is described in more detail in J. K. Beddow, ed., Particle Characterization in Technology, Vol 1, Applications and Microanalysis, CRC
  • a sonic sifter which separates particles according to size by a combination of a vertical oscillating column of air and a repetitive mechanical pulse on a sieve stack, can also be used to determine the particle size distribution of particles used in the process of this invention. Sonic sifters are described in, for example,
  • the average particle size may also be determined by a laser light scattering method, using, for example, a Malvern MasterSizer instrument. An average particle size may then be computed in various well-known ways, including:
  • Zj is the number of particles whose minimum length falls within an interval Lj.
  • average crystal size will be defined as a number average.
  • the particulate alumina used in the present process has a particle diameter which is smaller than that taught in conventional processes, including the grinding/homogenization step which is taught in, for example, U.S. Patent No. 5,208,005, the entire disclosure of which is inco ⁇ orated by reference for all pu ⁇ oses. While it is not detrimental to the present process to use a grinding/homogenization step during the practice ofthe present invention, it has been found that the best non-zeolitic molecular sieve, in terms of catalyst performance, is achieved when the particulate alumina which is added to the reaction mixture has an average particle size of less than 40 ⁇ prior to any reaction mixture grinding/homogenization step.
  • a non-zeolitic molecular sieve is preferably prepared according to the present process using a particulate hydrated alumina having a low alkali content.
  • alkali refers to the metallic elements in Group I A ofthe Periodic Table ofthe
  • CAS Chemical Engineers' Handbook, McGraw-Hill Book Company, 5th Ed., 1973, and includes, for example, the metals lithium, sodium, potassium, rubidium and cesium.
  • sodium is the alkali of primary concern in the preparation ofthe non- zeolitic molecular sieve, and the ratio of sodium to total alkali in the particulate alumina source and in the molecular sieve may be as high as 80%, 90% and even up to 100%.
  • the particulate hydrated alumina ofthe present process has a low alkali level, specifically a low sodium level, before it is added to the reaction mixture from which and in which the NZMS is prepared.
  • the particulate hydrated alumina useful for the present process contains less than about 0.12 wt% and preferably less than 0.10 wt% alkali. It is most preferred that the particulate hydrated alumina also have an alkali content in the range of about 0.01 wt%, to about 0.10 wt % where alkali may be one or more ofthe Group IA elements. This amount of alkali is significantly lower than what is present in available low alkali hydrated aluminas having an average particle size of less than about 40 ⁇ and a particle density of less than about 1.0 g/cm 3 . Typically, "low-alkali" hydrated aluminas currently available have an alkali content of greater than 0.25 wt%, which is significantly higher than that amount of alkali in the present hydrated alumina.
  • Alkali content may be suitably determined using atomic spectroscopy. Such methods are well known in the art, and it should not be necessary to describe them in detail here.
  • the finished non-zeolitic molecular sieve prepared using the present process contains less than 500 ppm by weight alkali, preferably in the range from about 75 to about 500 ppm alkali, more preferably in the range from 75 to about 400 ppm alkali, and most preferably from about 75 to about 325 ppm alkali.
  • the non-zeolitic molecular sieves which may be prepared using the present process are described, for example, in U.S. Patent No. 4,861,743, the disclosure of which, is completely inco ⁇ orated herein by reference for all pu ⁇ oses.
  • Non-zeolitic molecular sieves include aluminophosphates (AIPO4) as described in U.S. Patent No. 4,310,440, silicoaluminophosphates (SAPO), metalloaluminophosphates (MeAPO), and nonmetal substituted aluminophosphates (E1APO).
  • SAPO silicoaluminophosphates
  • MeAPO metalloaluminophosphates
  • E1APO nonmetal substituted aluminophosphates
  • Metalloaluminophophate molecular sieves are described in U.S. Patent Nos. 4,500,651; 4,567,029; 4,544, 143; 4,686,093 and 4,861,743.
  • Nonmetal substituted aluminophosphates are described in U.S. Patent No. 4,973,785.
  • the preferred non-zeolitic molecular sieve prepared as described herein is an intermediate pore silicoa
  • SAPO-11, SAPO-31, and SAPO-41 are preferred.
  • U.S. Patent No. 4,440,871 describes SAPO's generally and SAPO-11, SAPO-31, and SAPO-41 specifically.
  • a still more preferred intermediate pore isomerization silicoaluminophosphate molecular sieve prepared in the present process is SAPO-1 1.
  • the most preferred intermediate pore SAPO prepared by the present process is SM-3, which has a crystalline structure falling within that ofthe
  • SAPO-11 molecular sieves A preparation of SM-3 and its unique characteristics are described in U.S. Patent 5,158,665. As used herein, the term “non-zeolitic molecular sieve” and its abbreviation “NZMS” will be used interchangeably.
  • intermediate pore size an effective pore aperture in the range of about 5.3 to about 6.5 Angstroms when the molecular sieve is in the calcined form.
  • the effective pore size ofthe molecular sieves can be measured using standard adso ⁇ tion techniques and hydrocarbonaceous compounds of known minimum kinetic diameters. See Breck, Zeolite Molecular Sieves, 1974 (especially Chapter 8); Anderson et al., J. Catalysis 58, 114 (1979); and U.S. Pat. No. 4,440,871.
  • Intermediate pore size molecular sieves will typically admit molecules having kinetic diameters of 5.3 to 6.5 Angstroms with little hindrance.
  • n-hexane 4.3
  • 3- methylpentane 5.5
  • benzene 5.85
  • toluene 5.8
  • Compounds having kinetic diameters of about 6 to 6.5 Angstroms can be admitted into the pores, depending on the particular sieve, but do not penetrate as quickly and in some cases are effectively excluded.
  • Compounds having kinetic diameters in the range of 6 to 6.5 angstroms include: cyclohexane (6.0), 2,3-dimethylbutane (6.1), and m-xylene (6.1).
  • compounds having kinetic diameters of greater than about 6.5 Angstroms do not penetrate the pore apertures and thus are not absorbed into the interior ofthe molecular sieve lattice.
  • larger compounds include: o-xylene (6.8), hexamethylbenzene (7.1), and tributylamine (8.1).
  • the preferred effective pore size range is from about 5.5 to about 6.2 Angstroms.
  • the non-zeolitic molecular sieve prepared using this process is characterized by a three-dimensional microporous framework structure of AlO 2 , and PO 2 tetrahedral oxide units with a unit empirical formula on an anhydrous basis of:
  • M represents at least one element, other than aluminum and phosphorous, which is capable of forming an oxide in tetrahedral coordination with AlO 2 and PO 2 oxide structural units in the crystalline molecular sieve;
  • x, "y”, and “z” represent the mole fractions, respectively, of element "M”, aluminum, and phosphorus, wherein “x” has a value equal to or greater than zero (0), and "y” and “z” each have a value of at least 0.01.
  • metallic element "M” is selected from the group consisting of arsenic, beryllium, boron, chromium, cobalt, gallium, germanium, iron, lithium, magnesium, manganese, silicon, titanium, vanadium, nickel, and zinc, more preferably selected from the group consisting of silicon, magnesium, manganese, zinc, and cobalt; and still more preferably silicon.
  • the non-zeolitic molecular sieve as prepared herein may exist in any state or degree of hydration. It will be clear to one skilled in the art from the present disclosure that the non-zeolitic molecular sieve formed in the reaction mixture may be hydrated to some degree depending on the synthesis material used and on the amount of heat treatment applied to the crystalline molecular sieve. Both hydrated as well as anhydrous non- zeolitic molecular sieves are within the scope ofthe present invention.
  • an organic templating agent also known as a structure directing agent, is generally added to the reaction mixture to facilitate crystallization ofthe molecular sieve.
  • Organic templating agents can be selected from those known to be effective in the synthesis of crystalline molecular sieves and crystalline zeolites.
  • U.S. Patent Nos. 4,710,485; 4,440,871; 4,310,440; 4,567,029; 4,686,093; and 4,913,799 include examples of suitable templating agents.
  • the templating agents useful in the present invention contain elements of Group VA ofthe Periodic Table of Elements (CAS), particularly nitrogen, phosphorus, arsenic and antimony, preferably nitrogen or phosphorus and most preferably nitrogen.
  • the templating agents also contain at least one alkyl or aryl group having from 1 to 8 carbon atoms.
  • Particularly preferred nitrogen-containing compounds for use as templating agents are the amines and quaternary ammonium compounds, the latter being represented generally by the formula P N + wherein each R is an alkyl or aryl group containing from 1 to 8 carbon atoms.
  • Polymeric quaternary ammonium salts such as [(Ci4H 32 N 2 )(OH) 2 ] x wherein "x" has a value of at least 2 are also suitably employed. Both mono-, di- and triamines are advantageously utilized, either alone or in combination with a quaternary ammonium compound or other templating compound. Mixtures of two or more templating agents can either produce mixtures ofthe desired non-zeolitic molecular sieves or the more strongly directing templating species may control the course ofthe reaction with the other templating species serving primarily to establish the pH conditions ofthe reaction gel.
  • templating agents include tetramethyiammonium, tetraethylamonium, tetrapropylammonium or tetrabutylammonium ions; di-n-propylamine; di-isopropylamine; tripropylamine; triethylamine, triethanolamine, piperidine; cyclohexylamine; 2-methylethanolamine; choline; NiN-dimethylbenzylamine; N
  • non-zeolitic molecular sieve i.e., a single templating agent can, with proper manipulation ofthe reaction conditions, direct the formation of several non-zeolitic molecular sieve compositions, and a given non-zeolitic molecular sieve composition can be produced using several different templating agents.
  • phosphoric acid is the preferred source of phosphorous.
  • Organic phosphates and a crystalline aluminophosphate can also be employed as a source of phosphorous.
  • Silica sol or fumed silica are preferred sources of silicon.
  • Silica gel, alkoxides of silicon, and reactive solid amo ⁇ hous precipitated silica are also suitable.
  • Preferred sources ofthe optional element “M” include any elemental or compound form of element “M” which will form oxide units in tetrahedral coordination in the molecular sieve without being detrimental to the integrity ofthe molecular sieve.
  • Salts of element "M”, including halogen, nitrate, sulfate, oxide, sulfides, acetate and oxalate salts are examples of active sources of element "M” which may be used in the present process.
  • the reaction mixture from which the NZMS is made expressed in terms of molar oxide ratios on an anhydrous basis, has the following preferred bulk composition: aR:(M x Al y P I )O 2 :bH 2 O
  • R is a template, "a” has a value great enough to constitute an effective concentration of “R” and is within the range of from greater than zero (0) to about 3; “b” has a value of from zero to 500;
  • "x", "y”, and “z” represent the mole fractions, respectively, of element "M", aluminum, and phosphorus wherein “x” has a value equal to or greater than zero (0), and "y” and “z” each have a value of at least 0.01, and wherein "M” represents at least one element, other than aluminum and phosphorous, which is capable of forming an oxide in tetrahedral coordination with AlO 2 and PO 2 .
  • a preferred synthesis method of this invention comprises:
  • a more preferred method for according to the instant process comprises:
  • reaction mixture containing phosphoric acid, a reactive source of SiO 2 , an organic templating agent and a particulate hydrated alumina having an average particle size of less than 40 ⁇ , a particle density of less than about 1.0 g cm 3 and an alkali content of less than 0.12 wt%, said reaction mixture having a composition expressed in terms of mole ratios of:
  • R is an organic templating agent
  • "a” has a value large enough to constitute an effective amount of R and preferably has a value such that there are from 0.20 to 2 moles of R per mole of aluminum oxide
  • "b” has a value such that there are zero (0) to 100 moles of H 2 O per mole of aluminum oxide; said reaction mixture having been formed by combining the alumina and phosphorous sources in the substantial absence ofthe silicon source and thereafter combining the resulting mixture with the silicon source and the organic templating agent to form the complete reaction mixture;
  • reaction mixture having a composition expressed in terms of molar oxide ratios as follows: aR : (M x Al y P z ) ⁇ 2:bH 2 O
  • R is a templating agent
  • a has a value great enough to constitute an effective concentration of "R” and is within the range of greater than 0 to 6
  • "b” has a value of zero to 500, preferably 2 to 30
  • M represents magnesium or cobalt
  • x represents magnesium or cobalt
  • x represents magnesium or cobalt
  • x represents aluminum and phosphorous in the (M x AlyP z ) ⁇ 2 constituent, and each has a value of at least 0.01.
  • water is added to facilitate crystallization and subsequent processing.
  • the molar ratio of water to alumina in the reaction mixture is in the range of from about zero to about 8, preferably from about 1 to about 6.
  • sufficient water is added to the reaction mixture prior to crystallization so that the reaction mixture may be adequately blended and may be formed into self-supporting particles. Beyond that amount of water, no additional water is required for crystallization. This method is described in detail in U.S. Patent Number 5,514,362.
  • an aqueous reaction mixture is prepared containing active sources ofthe NZMS, including sources of alumina, phosphorous and optionally an element other than aluminum and phosphorous to be incorporated into the crystalline molecular sieve. Frequently, a templating agent will also be present.
  • the amount of water added to the reaction mixture in this embodiment is generally less than about 500 moles of water per mole of alumina, preferably from about 8 to about 100, more preferably from about 10 to about 50, moles of water per mole of alumina.
  • the pH ofthe reaction mixture may be adjusted as required for the synthesis ofthe desired molecular sieve.
  • the reaction mixture from which siiicoaluminophosphates are prepared will typically have an initial pH in the range of about 4.0 to about 8.5.
  • Crystallization ofthe molecular sieve is conducted at hydrothermai conditions under pressure and usually in an autoclave so that the reaction mixture is subject to autogenous pressure and preferably with stirring.
  • the reaction mixture containing the crystallized molecular sieve is filtered if sufficient free liquid water is present and the recovered crystals are washed, for example, with water, and then dried, such as by heating at from 25°C to 150°C at atmospheric pressure.
  • any supematant liquid above the crystals is removed prior to the initial filtering ofthe crystals.
  • the molecular sieve prepared by the present method is beneficially subjected to thermal treatment to remove the organic templating agent.
  • This thermal treatment is generally performed by heating at a temperature of 300°C to 800°C for at least 1 minute and generally not longer than 20 hours. While subatmospheric pressure can be employed for the thermal treatment, atmospheric pressure is desired for reasons of convenience.
  • the thermally treated product is particularly useful in the catalysis of certain hydrocarbon conversion reactions.
  • the non-zeolitic molecular sieve can be used in intimate combination with hydrogenating components, such as tungsten, vanadium, molybdenum, rhenium, nickel, cobalt, chromium, manganese, or a noble metal, such as palladium, platinum, rhodium, rhenium, iridium or mixtures thereof, for those applications in which a hydrogenation- dehydrogenation function is desired.
  • a noble metal such as palladium, platinum, rhodium, rhenium, iridium or mixtures thereof, for those applications in which a hydrogenation- dehydrogenation function is desired.
  • Group VIII metals selected from the group consisting of at least one of platinum and palladium are preferred.
  • the amount of metal ranges from about 0.01% to about 10% by weight ofthe molecular sieve, preferably from about 0.2 to about 5 % by weight ofthe molecular sieve.
  • Hydrogen, ammonium, and the metal components can be exchanged into the molecular sieve.
  • the molecular sieve can also be impregnated with the metals, or the metals can be physically intimately admixed with the molecular sieve using standard methods known to the art.
  • the metals can be occluded in the crystal lattice by having the desired metals present as ions in the reaction mixture from which the molecular sieve is prepared.
  • metal or “active metal” as used herein means one or more metals in the elemental state or in some form such as sulfide, oxide and mixtures thereof. Regardless of the state in which the metallic component actually exists, the concentrations are computed as if they existed in the elemental state.
  • the molecular sieve may be calcined in air or inert gas at temperatures ranging from about 200°C. to 700°C. for periods of time ranging from 1 to 48 hours, or more, to produce a catalytically active product especially useful in hydrocarbon conversion processes.
  • the non-zeolitic molecular sieve may be used as a catalyst, without additional forming, when the shaped particles, formed from the reaction mixture described hereinbefore, are of a size and shape desired for the ultimate catalyst.
  • the molecular sieve can be composited with one or more of materials resistant to the temperatures and other conditions employed in organic conversion processes, using techniques such as spray drying, extrusion, and the like.
  • matrix materials include active and inactive materials and synthetic or naturally occurring zeolites as well as inorganic materials such as silica, clays and metal oxides such as alumina, magnesia, and titania.
  • zeolites examples include synthetic and natural faujasites (e.g., X and Y), erionites, mordenites, and those ofthe ZSM series, e.g., ZSM-5, etc.
  • the combination of zeolites can also be composited in a porous inorganic matrix.
  • the inorganic materials may occur naturally or may be in the form of gelatinous precipitates, sols, or gels, including mixtures of silica and metal oxides.
  • Use of an active material in conjunction with the synthetic molecular sieve, i.e., combined with it, tends to improve the conversion and selectivity ofthe catalyst in certain organic conversion processes.
  • Inactive materials can suitably serve as diluents to control the amount of conversion in a given process so that products can be obtained economically without using other means for controlling the rate of reaction.
  • molecular sieve materials have been inco ⁇ orated into naturally occurring clays, e.g., bentonite and kaolin. These materials, i.e., clays, oxides, etc., function, in part, as binders for the catalyst. It is desirable to provide a catalyst having good crush strength, because in petroleum refining the catalyst is often subjected to rough handling. This tends to break the catalyst down into powders which cause problems in processing.
  • Naturally occurring clays which can be composited with the new crystal include the montmorillonite and kaolin families which include the subbentonites, and the kaolins commonly known as Dixie, McNamee, Georgia, and Florida clays or others in which the main mineral constituent is halloysite, kaolinite, dickite, nacite, or an auxite. Such clays can be used in the raw state as originally mined or initially subjected to calcination, acid treatment, or chemical modification. Binders useful for compositing with the present crystal also include inorganic oxides, notably alumina or silica.
  • the non-zeolitic molecular sieve produced can be composited with a porous matrix material such as aluminum phosphate, silica- alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania as well as ternary compositions such as silica-alumina-thoria, silica-alumina-zirconia, silica-alumina- magnesia, and silica-magnesia-zirconia.
  • a porous matrix material such as aluminum phosphate, silica- alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania as well as ternary compositions such as silica-alumina-thoria, silica-alumina-zirconia, silica-alumina- magnesia, and si
  • the relative proportions of finely divided crystalline non-zeolitic molecular sieve material and inorganic oxide gel matrix vary widely, with the crystal content ranging from 1 to 90% by weight, and more particularly when the composite is prepared in the form of beads, in the range of 2 to 80 weight percent ofthe composite.
  • Non-zeolitic molecular sieves prepared in the present process are useful for a variety of organic, e.g., hydrocarbon compound conversion processes.
  • Hydrocarbon conversion reactions are chemical and catalytic processes in which carbon containing compounds are changed to different carbon containing compounds. Examples of hydrocarbon conversion reactions include catalytic cracking, hydrocracking, dewaxing, and olefin and aromatics formation reactions, including formation from oxygenates.
  • the catalysts are useful in other petroleum refining and hydrocarbon conversion reactions such as isomerizing and hydroisomerizing paraffins and olefins, polymerizing and oligomerizing olefinic or acetylinic compounds such as isobutylene and pentene- 1 , reforming, alkylating, isomerizing polyalkylsubstituted aromatics (e.g. meta xylene), and disproportionating aromatics (e.g. toluene) to provide mixture of benzene, xylenes and higher methylbenzenes.
  • isomerizing and hydroisomerizing paraffins and olefins polymerizing and oligomerizing olefinic or acetylinic compounds such as isobutylene and pentene- 1
  • the molecular sieve prepared in the present process can be used in a process to dewax hydrocarbonaceous feeds.
  • the catalytic dewaxing conditions are dependent in large measure on the feed used and upon the desired pour point.
  • the temperature will be between about 200° C. and about 475° C, preferably between about 250° C. and about 450° C.
  • the pressure is typically between about 200 psig and 3000 psig.
  • the liquid space velocity (LHSV) preferably will be from 0.1 to 20, preferably between about 0.2 and about 10.
  • Hydrogen is preferably 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), preferably about 1000 to about 20,000 SCF/bbl. Generally, hydrogen will be separated from the product and recycled to the reaction zone.
  • the present dewaxing process provides selective conversion of waxy n-paraffins to non-waxy products of higher molecular weight when compared to products obtained using the prior art zeolitic catalyst.
  • the n- paraffins and the slightly branched paraffins undergo some cracking or hydrocracking to form liquid range materials which contribute to a low viscosity product.
  • the degree of cracking which occurs is, however, limited so that the gas yield is reduced, thereby preserving the economic value ofthe feedstock.
  • the dewaxing process may be used to dewax a variety of feedstocks ranging from relatively light distillate fractions up to high boiling stocks such as whole crude petroleum, reduced crudes, vacuum tower residua, cycle oils, synthetic crudes (e.g., shale oils, tars and oils, etc.), gas oils, vacuum gas oils, foot oils, and other heavy oils.
  • feedstock will normally be a C ⁇ o+ feedstock generally boiling above about 350° F.
  • waxy distillate stocks such as middle distillate stocks including gas oils, kerosenes, and jet fuels, lubricating oil stocks, heating oils and other distillation fractions whose pour point and viscosity need to be maintained within certain specification limits.
  • Lubricating oil stocks will generally boil above 230° C. (450° F.), more usually above 315° C. (600° F.).
  • Hydroprocessed stocks which include stocks which have been hydrotreated to lower metals, nitrogen and sulfur levels and/or hydrocracked, are a convenient source of stocks of this kind and also of other distillate fractions since they normally contain significant amounts of waxy n-paraffins.
  • the process herein can be practiced with utility when the feed contains organic nitrogen (nitrogen-containing impurities), it is preferred that the organic nitrogen content ofthe feed be less than 50, more preferably less than 10, ppmw.
  • the NZMS catalyst may be used to isomerize a waxy feedstock.
  • the waxy feedstock preferably contains greater than about 50% wax, more preferably greater than about 90% wax.
  • a highly paraffinic feed having a high pour point, generally above about 0° C, more usually above about 10° C, but containing less than 50% wax is also suitable for use in the process ofthe invention.
  • Such a feed should preferably contain greater than about 70% paraffinic carbon, more preferably greater than about 80% paraffinic carbon, most preferably greater than about 90% paraffinic carbon.
  • Exemplary additional suitable feeds for use in the process ofthe invention include waxy distillate stocks such as gas oils, lubricating oil stocks, synthetic oils such as those by Fischer-Tropsch synthesis, high pour point polyalphaolefins, foots oils, synthetic waxes such as normal alphaolefin waxes, slack waxes, deoiled waxes and microcrystalline waxes.
  • Foots oil is prepared by separating oil from the wax. The isolated oil is referred to as foots oil.
  • Slack wax can be obtained from either a hydrocracked lube oil or a solvent refined lube oil. Hydrocracking is preferred because that process can also reduce the nitrogen content to low values. With slack wax derived from solvent refined oils, deoiling can be used to reduce the nitrogen content. Optionally, hydrotreating ofthe slack wax can be carried out to lower the nitrogen content thereof.
  • Slack waxes possess a very high viscosity index, normally in the range of from 140 to 200, depending on the oil content and the starting material from which the wax has been prepared. Slack waxes are therefore eminently suitable for the preparation of lubricating oils having very high viscosity indices, i.e., from about 120 to 180.
  • the pour point ofthe dewaxed product is lower than the pour point ofthe feed to the dewaxing process.
  • the pour point ofthe oil is generally below about 10°C, and often below 0°C. Indeed, with the proper choice of dewaxing conditions and feedstock, a pour point below -24° C. (generally between -24° C. and -63° C.) can be achieved.
  • the viscosity index ofthe dewaxed oil is not critical to the dewaxing process, it is a feature ofthe dewaxing process using the present catalyst that the viscosity index ofthe feedstock is not adversely affected, and is indeed often improved, in the dewaxing process. This is in contrast to conventional dewaxing processes using zeolite catalysts, in which the viscosity index is frequently reduced during dewaxing.
  • the viscosity index ofthe dewaxed oil will generally be above 90.
  • a viscosity index between 125 and 180 can be achieved.
  • the non-zeolitic molecular sieve When used in the dewaxing process, the non-zeolitic molecular sieve is employed in admixture with at least one group VIII metal as, for example, the noble metals such as platinum and palladium, and optionally other catalytically active metals such as nickel, tungsten, molybdenum, cobalt, vanadium, zinc, etc.
  • group VIII metal such as platinum and palladium
  • other catalytically active metals such as nickel, tungsten, molybdenum, cobalt, vanadium, zinc, etc.
  • the amount of metal ranges from about 0.01% to 10% and preferably 0.2 to 5% by weight ofthe molecular sieve.
  • the Group VIII metal utilized in the process of this invention can mean one or more ofthe metals in its elemental state or in some form such as the sulfide or oxide and mixtures thereof.
  • the active metal or metals when referring to the active metal or metals, it is intended to encompass the existence of such metal in the elementary state or in some form such as the oxide or sulfide as mentioned above, and regardless of the state in which the metallic component actually exists, the concentrations are computed as if they existed in the elemental state.
  • the NZSM can be used in a process to prepare lubricating oils.
  • the process comprises (a) hydrocracking in a hydrocracking zone a hydrocarbonaceous feedstock to obtain an effluent comprising a hydrocracked oil, and (b) catalytically dewaxing in a catalytic dewaxing zone the hydrocracked oil of step (a) with a catalyst comprising a non- zeolitic molecular sieve and a Group VIII metal, preferably platinum or palladium.
  • Another embodiment of this process includes an additional step of stabilizing said dewaxed hydrocrackate by catalytic hydrofinishing.
  • the hydrocarbonaceous feeds from which lube oils are made usually contain aromatic compounds as well as normal and branched paraffins of very long chain lengths.
  • the feeds usually boil in the gas oil range.
  • Preferred feedstocks are vacuum gas oils with normal boiling ranges in the range of 350° C. to 600° C, and deasphalted residual oils having normal boiling ranges from about 480° C. to 650° C.
  • Reduced topped crude oils, shale oils, liquefied coal, coke distillates flash or thermally cracked oils, atmospheric residua, and other heavy oils can also be used.
  • the first step in the processing scheme is hydrocracking. In commercial operations, hydrocracking can take place as a single-step in the process, or as a multistep process using initial denitrification or desulfurization steps, all of which are well known.
  • a typical hydrocracking process is described, for example, in U.S. Patent No. 5,158,665, the entire disclosure of which is inco ⁇ orated herein by reference. It may further be desired to hydrofinish the dewaxed oil in a mild hydrogenation process to produce more stable lubrication oils.
  • a description of a typical hydrofinishing process and catalyst which is useful in the present process is also taught in U.S. Patent No. 5,158,665.
  • Example 1 SAPO-11 was prepared as follows: a reaction mixture was prepared by combining 502 grams of 86% H 3 PO4 with 320 grams of deionized ice in a Teflon beaker in a cold water bath. To the reaction mixture were slowly added 129 grams of Al(OH) 3 (52 wt% AI 2 O 3 ) with 577 grams of cold deionized water while simultaneously mixing with a stirrer and grinding with a Polytron. The Al(OH) 3 , F-2000: R254-30 alumina hydroxy carbonate supplied by Reheis Inc. (New Jersey), had an average particle diameter of 9.4 microns (by Malvern particle size analysis). The sodium content ofthe Al(OH) 3 was about 0.08 wt%. The particle density ofthe Al(OH) 3 was 0.57 g/cm 3 .
  • Example 1 The sieve of Example 1 was impregnated with 0.5 wt% platinum and tested in a continuous-flow high-pressure pilot plant for lowering the pour point of a hydrocracked heavy neutral oil (Table I). Run conditions were 2.3 hr '1 WHSV (weight hourly space velocity), 1950 psi (13.5 MPa) total pressure, and 8 MSCF/bbl once-through H 2 (1425 std m 3 H ⁇ /m 3 oil). Results are shown in Table II.
  • Example 3 80 grams ofthe 4.7 micron Reheis Al(OH) 3 from Example 1 were placed in a small Baker-Perkins mixer. To this were added 8 grams of water and 89.8 grams of 86% H 3 PO 4 , followed by 9.6 grams of filmed silica (Cabosil M-5) and 14 grams of peptized and neutralized Catapal alumina (40 wt% Al 2 O 3 , 60 wt% H 2 O), the latter to serve as a binder and to facilitate extrusion. After about 2 hours of mixing, 28.8 grams of a 3/1 template mixture of di-n-propylamine and di-isopropylamine were added with mixing.
  • filmed silica Cabosil M-5
  • Catapal alumina 40 wt% Al 2 O 3 , 60 wt% H 2 O
  • Example 4 The catalyst of Example 3 was impregnated with 0.5 wt% Pt and tested for lowering the pour point ofthe waxy hydrocracked heavy neutral feedstock of Table I.
  • Example 5 502 grams of 86% H 3 PO4 were placed in a stainless steel bucket'in an ice bath. To the bucket were added 120 grams of deionized ice and 600 grams of cold water. To this were slowly added 129 grams of Al(OH) 3 (Reheis F-2000: R254-27 Al(OH) 3 with a sodium content of 0.04 wt%) along with 577 grams of cold deionized water while simultaneously mixing with a stirrer and grinding with a Polytron.
  • Example 6 The sieve of Example 5 was mixed with 15 wt % (volatiles free) peptized Catapal alumina and extruded through a 1/16-inch die. The extrudate was dried in an oven at 66°C for one hour, 93°C for one hour, and 121°C for three hours, and then calcined in flowing air at 454°C for four hours. The extrudate was then impregnated with 0.4 wt % platinum using an aqueous solution of Pt(NH 3 ) 4 Cl2 The extrudate was dried at 66°C for three hours, and then calcined in flowing air at 288°C for four hours.
  • the catalyst was crushed to 24-42 mesh and tested for lowering the pour point of the feed of Table 1. Run conditions were 1.6 hr "1 LHSV (liquid hourly space velocity), 1950 psi (13.5 MPa) total pressure, and 8 MSCF/bbl once-through H 2 (1425 std m 3
  • Comparative Example 1 SAPO- 11 was prepared similar to Example 3 except that the Reheis Al(OH) 3 was substituted by 56 grams of a hydrated aluminum oxide (pseudo-boehmite, 73 wt% Al 2 O 3 , 37 wt% H 2 O) containing 70 ppm sodium.
  • the average particle diameter ofthe hydrated aluminum oxide was 134 microns, and the particle density approximately 1.3 g/cm 3 .
  • the catalyst was impregnated with Pt and tested for dewaxing as in Example 4. At a catalyst temperature of 720°F (382°C), the product pour point was -3°C, showing less pour point reduction than a catalyst of this invention at the same reactor temperature.
  • the following example illustrates the effect of using a hydrated alumina having an alkali content outside the range ofthe alumina source ofthe present invention.
  • Comparative Example 2 SAPO-11 was prepared as in Example 5 with the exception that the Al(OH) 3 contained a sodium level of 0.14 wt %.
  • the calcined sieve had the same composition as the sieve of Example 5 but with a sodium content of 530 ppm.
  • the following example illustrates the effect of using a hydrated alumina having an alkali content outside the range ofthe alumina source ofthe present invention, and illustrates the effect on catalyst performance of removing alkali from the finished non- zeolitic molecular sieve.
  • Comparative Example 3 SAPO-11 was prepared as in Example 1 with the exception that the Al(OH) 3 (Reheis F-2000 alumina hydroxy carbonate having the same physical properties as that used in Example 1, but with higher sodium content) contained a sodium level of 0.25 wt %.
  • the calcined sieve had the following anhydrous molar composition:
  • Comparative Example 4 502 grams of 86% H 3 PO 4 were added to a stainless steel bucket cooled in an ice bath. 240 grams of deionized ice were then added with stirring. 105 grams of Catapal alumina (73 wt% Al 2 O 3 , 27 wt% H 2 O), and 791 grams of deionized ice were slowly added with stirring and grinding over a 90-minute time period.
  • the Catapal as used had a particle density of approximately 1.3 g/cm 3 . At that point, the viscosity ofthe mix, measured at 16°C, had risen to 29,000 cp. 98 grams of di-n-propylamine were then added. 192 more grams of alumina were added (to bring the Al/P mole ratio to 0.97) along with 250 grams of ice.
  • the mixture had the following composition, expressed in molar ratio of oxides:
  • Comparative Example 5 SAPO-11 was prepared according to Example 1 of U.S. Patent No. 5,246,566.
  • the alumina source was aluminum isopropoxide (Al[OC 3 H 7 ] 3 ), and the sodium content of the resulting SAPO- 11 was found to be approximately 40 ppm.
  • This comparative example shows that SAPO-1 1 made using a known source of alumina had a sodium level below that ofthe present non-zeolitic molecular sieve.

Abstract

This invention provides a method for preparing non-zeolitic molecular sieves using inexpensive reagents and at lower manufacturing cost. The method includes using a low density, small size particulate hydrated alumina, such as aluminum hydroxide, in place of aluminum alkoxides and other more costly reagents. The preferred particulate hydrated alumina has a density of less than 1.0 g/cm3, an average particle size of less than about 40 microns and an alkali content of less than 0.12 wt.%.

Description

ALUMINA SOURCE FOR NON-ZEOLITIC MOLECULAR SIEVES
This invention relates to the synthesis of non-zeolitic molecular sieves. It more particularly relates to a method of preparing non-zeolitic molecular sieves (NZMS) at low cost and with simplified processing.
The non-zeolitic molecular sieves to which the present invention is directed comprise crystalline, three-dimensional microporous framework structures of tetrahedrally-bound AlO2 and PO2 oxide units, and optionally one or more metals in tetrahedral coordination with oxygen atoms. See U.S. Patent No. 4,861,743. The crystalline aluminophosphate-type materials which are prepared by the present process are useful, inter alia, for a number of catalytic conversion processes, including dewaxing, isomerization, hydroisomerization, hydrocracking, hydrogenation.
A non-zeolitic molecular sieve is prepared from a reaction mixture comprising active sources ofthe molecular sieve, including active source(s) of aluminum and phosphorous. A preferred active source of alumina in the conventional preparation ofthe non-zeolitic molecular sieves is an aluminum alkoxide, such as aluminum isopropoxide, or a pseudo-boehmite hydrated aluminum oxide. U.S. Patent No. 4,310,440, which discloses aluminum phosphate molecular sieves, and U.S. Patent No. 4,440,871, which discloses silicoaluminophosphates and their preparation, list these sources of aluminum for the preparation of these molecular sieves.
While other alumina sources have been taught, none have been shown to produce non-zeolitic molecular sieves having catalytic properties, such as catalyst activity and selectivity in the conversion of petroleum and organic feedstocks, equal to that of a non- zeolitic molecular sieve prepared using an aluminum alkoxide as the alumina source. However, aluminum alkoxides are expensive relative to other alumina sources.
Furthermore, in the use of aluminum alkoxides in the preparation of non-zeolitic molecular sieves, a waste stream rich in alcohols is produced; this waste stream must be treated or disposed, at additional processing expense. An improved method for preparing a non-zeolitic molecular sieve is desired. It is therefore an object ofthe present invention to provide a non-zeolitic molecular sieve (NZMS), which has high activity and selectivity in the conversion of petroleum and organic feedstocks, and which is prepared using reagents which are less costly than those used in conventional preparation methods. It is a further object ofthe present invention to provide an improved process for preparing a non-zeolitic molecular sieve using a particulate hydrated alumina, such as Al(OH)3, as the alumina source. It is a further object ofthe present invention to provide an improved molecular sieve at reduced manufacturing cost and with simplified operation.
The present invention is based in part on the surprising discovery that an improved non-zeolitic molecular sieve having good catalytic activity and selectivity may be prepared using a low cost hydrated alumina source, preferably a particulate hydrated alumina having a small particle size, a low particle density, and a low alkali content. The particle size ofthe preferred hydrated alumina source is smaller than that previously taught for the preparation of non-zeolitic molecular sieves, and the alkali content (including sodium) of the preferred particulate alumina is lower than that normally found in low-cost alumina sources. Further to the surprise is the discovery that a non-zeolitic molecular sieve having an alkali content within the present range has comparable catalytic performance to a non- zeolitic molecular sieve prepared with an expensive alumina source which is substantially free of alkali.
The present invention is directed to a process, and the produced product, for preparing a molecular sieve comprising maintaining a reaction mixture containing an active source of phosphorous and a particulate hydrated alumina under crystallization conditions until crystals ofthe molecular sieve form, the particulate hydrated alumina having an average particle size of less than about 40μ, a particle density of less than about 1.0 g/cm3 and an alkali content of less than about 0.12% by weight.
The particulate hydrated alumina for this process preferably has an average particle size of less than about 25 μ and more preferably less than about lOμ, with preferably less than about 25% ofthe particulates having an average particle size outside of a range of about O.lμ to about 40μ. The most preferred particulate hydrated alumina has an average particle size within a range of about 0. lμ to about lOμ, with less than 25% and preferably less than 10% ofthe particles having an average particle size outside of a range of about 0. lμ to about 25μ. A preferred particulate hydrated alumina for this process has a particle density of less than about 0.9 g/cm3, more preferably less than about
0.8 g/cm3,.and most preferably in the range of about 0.1 g cm3 to about 0.8 g/cm3 In a separate embodiment, the present invention is directed to a molecular sieve prepared using a process comprising maintaining a reaction mixture containing an active source of phosphorous and a particulate hydrated alumina under crystallization conditions until crystals ofthe molecular sieve form, the particulate hydrated alumina having an average particle size of less than about 40μ, a particle density of less than about 1.0 g/cm3 and an sodium content of less than 0.12 wt%. In a further embodiment, the present invention is directed to a non-zeolitic molecular sieve which contains less than 500 ppm, preferably from about 75 to about 500 ppm alkali, more preferably from about 75 to about 400 ppm alkali and most preferably from about 75 to about 225 ppm alkali. The present process for preparing crystalline materials containing oxides of aluminum and phosphorous in tetrahedral coordination is characterized in part by the use of a source of alumina which is both cheaper and easier to use than the conventional sources, while producing non-zeolitic molecular sieves having catalytic properties which approach, are equal to or exceed the properties ofthe best non-zeolitic molecular sieves prepared using conventional sources.
The particulate hydrated alumina used in the present process for preparing a non- zeolitic molecular sieve has a particle density of less than about 1.0 g/cm3, preferably less than about 0.9 g/cm3, more preferably less than about 0.8 g/cm3 and most preferably in the range of about 0.1 g cm3 to about 0.8 g/cm3. The low density particulate alumina includes hydrated aluminas having an H2O/AI2O3 molar ratio of Al2θ3:nH2O, where n is greater than 2.2, preferably greater than 2.6, more preferably greater than 2.8. An example hydrated alumina useful in the present process is Reheis (Berkeley Heights, N.J.) F-2000 aluminum hydroxy carbonate, containing up to 10% carbonate and having an Al2O3:H2O molar ratio corresponding approximately to Al(OH)3, or Al2O3.3H2O. The particulate hydrated alumina, as added to the reaction mixture in which the non-zeolitic molecular sieve is formed, further has an average particle size of less than about 40μ, preferably less than about 25μ, more preferably less than about 15μ, still more preferably less than about lOμ, and most preferably within the range of about 0. lμ to about lOμ, with preferably less than about 25% ofthe particulates having a particle size outside of a range of about 0. Iμ to about 40μ. In the more preferred embodiment, less than about 25%, even more preferably less than 10% ofthe particles have a particle size outside of a range of about 0. lμ to about 25μ. As used herein, the symbol "μ" represents a measure of length in microns or, in the alternative, micrometers. In terms of particle size ofthe small particles described herein, this measure of length is a measure ofthe nominal or average diameters ofthe particles, assuming that they approximate a spherical shape, or, in the case of elongated particles have a circular cross-section. A variety of analytical methods are available to practitioners for determining the size of small particles. One such method employs a Coulter Counter, which uses a current generated by platinum electrodes on two sides of an aperture to count the number, and determine the size, of individual particles passing through the aperture. The Coulter Counter is described in more detail in J. K. Beddow, ed., Particle Characterization in Technology, Vol 1, Applications and Microanalysis, CRC
Press, Inc, 1984, pp. 183-6, and in T. Allen, Particle Size Measurement, London: Chapman and Hall, 1981, pp. 392-413. A sonic sifter, which separates particles according to size by a combination of a vertical oscillating column of air and a repetitive mechanical pulse on a sieve stack, can also be used to determine the particle size distribution of particles used in the process of this invention. Sonic sifters are described in, for example,
T. Allen, Particle Size Measurement, London: Chapman and Hall, 1981, pp. 175-176. The average particle size may also be determined by a laser light scattering method, using, for example, a Malvern MasterSizer instrument. An average particle size may then be computed in various well-known ways, including:
Number Average =
Figure imgf000006_0001
wherein Zj is the number of particles whose minimum length falls within an interval Lj. For puφoses of this invention, average crystal size will be defined as a number average.
The particulate alumina used in the present process has a particle diameter which is smaller than that taught in conventional processes, including the grinding/homogenization step which is taught in, for example, U.S. Patent No. 5,208,005, the entire disclosure of which is incoφorated by reference for all puφoses. While it is not detrimental to the present process to use a grinding/homogenization step during the practice ofthe present invention, it has been found that the best non-zeolitic molecular sieve, in terms of catalyst performance, is achieved when the particulate alumina which is added to the reaction mixture has an average particle size of less than 40μ prior to any reaction mixture grinding/homogenization step.
A non-zeolitic molecular sieve is preferably prepared according to the present process using a particulate hydrated alumina having a low alkali content. As used herein, the term alkali refers to the metallic elements in Group I A ofthe Periodic Table ofthe
Elements (CAS), a copy of which may be found in the inside front cover ofthe R H. Perry and CH. Chilton, eds, Chemical Engineers' Handbook, McGraw-Hill Book Company, 5th Ed., 1973, and includes, for example, the metals lithium, sodium, potassium, rubidium and cesium. In practice, sodium is the alkali of primary concern in the preparation ofthe non- zeolitic molecular sieve, and the ratio of sodium to total alkali in the particulate alumina source and in the molecular sieve may be as high as 80%, 90% and even up to 100%. It has been suφrisingly discovered that conventional methods of removing sodium and other alkali contaminants from a finished NZMS, such as by ion-exchange after calcination, tend to damage the crystal structure ofthe NZMS and to degrade its catalytic properties. For this and other reasons, the particulate hydrated alumina ofthe present process has a low alkali level, specifically a low sodium level, before it is added to the reaction mixture from which and in which the NZMS is prepared.
The particulate hydrated alumina useful for the present process contains less than about 0.12 wt% and preferably less than 0.10 wt% alkali. It is most preferred that the particulate hydrated alumina also have an alkali content in the range of about 0.01 wt%, to about 0.10 wt % where alkali may be one or more ofthe Group IA elements. This amount of alkali is significantly lower than what is present in available low alkali hydrated aluminas having an average particle size of less than about 40μ and a particle density of less than about 1.0 g/cm3. Typically, "low-alkali" hydrated aluminas currently available have an alkali content of greater than 0.25 wt%, which is significantly higher than that amount of alkali in the present hydrated alumina.
Alkali content may be suitably determined using atomic spectroscopy. Such methods are well known in the art, and it should not be necessary to describe them in detail here. The finished non-zeolitic molecular sieve prepared using the present process contains less than 500 ppm by weight alkali, preferably in the range from about 75 to about 500 ppm alkali, more preferably in the range from 75 to about 400 ppm alkali, and most preferably from about 75 to about 325 ppm alkali. The non-zeolitic molecular sieves which may be prepared using the present process are described, for example, in U.S. Patent No. 4,861,743, the disclosure of which, is completely incoφorated herein by reference for all puφoses. Non-zeolitic molecular sieves include aluminophosphates (AIPO4) as described in U.S. Patent No. 4,310,440, silicoaluminophosphates (SAPO), metalloaluminophosphates (MeAPO), and nonmetal substituted aluminophosphates (E1APO). Metalloaluminophophate molecular sieves are described in U.S. Patent Nos. 4,500,651; 4,567,029; 4,544, 143; 4,686,093 and 4,861,743. Nonmetal substituted aluminophosphates are described in U.S. Patent No. 4,973,785. The preferred non-zeolitic molecular sieve prepared as described herein is an intermediate pore silicoaluminophosphate or SAPO. More preferred SAPO's include
SAPO-11, SAPO-31, and SAPO-41. U.S. Patent No. 4,440,871 describes SAPO's generally and SAPO-11, SAPO-31, and SAPO-41 specifically. A still more preferred intermediate pore isomerization silicoaluminophosphate molecular sieve prepared in the present process is SAPO-1 1. The most preferred intermediate pore SAPO prepared by the present process is SM-3, which has a crystalline structure falling within that ofthe
SAPO-11 molecular sieves. A preparation of SM-3 and its unique characteristics are described in U.S. Patent 5,158,665. As used herein, the term "non-zeolitic molecular sieve" and its abbreviation "NZMS" will be used interchangeably.
By "intermediate pore size", as used herein, is meant an effective pore aperture in the range of about 5.3 to about 6.5 Angstroms when the molecular sieve is in the calcined form. The effective pore size ofthe molecular sieves can be measured using standard adsoφtion techniques and hydrocarbonaceous compounds of known minimum kinetic diameters. See Breck, Zeolite Molecular Sieves, 1974 (especially Chapter 8); Anderson et al., J. Catalysis 58, 114 (1979); and U.S. Pat. No. 4,440,871. Intermediate pore size molecular sieves will typically admit molecules having kinetic diameters of 5.3 to 6.5 Angstroms with little hindrance. Examples of such compounds (and their kinetic diameters in Angstroms) are: n-hexane (4.3), 3- methylpentane (5.5), benzene (5.85), and toluene (5.8). Compounds having kinetic diameters of about 6 to 6.5 Angstroms can be admitted into the pores, depending on the particular sieve, but do not penetrate as quickly and in some cases are effectively excluded. Compounds having kinetic diameters in the range of 6 to 6.5 angstroms include: cyclohexane (6.0), 2,3-dimethylbutane (6.1), and m-xylene (6.1). generally, compounds having kinetic diameters of greater than about 6.5 Angstroms do not penetrate the pore apertures and thus are not absorbed into the interior ofthe molecular sieve lattice. Examples of such larger compounds include: o-xylene (6.8), hexamethylbenzene (7.1), and tributylamine (8.1). The preferred effective pore size range is from about 5.5 to about 6.2 Angstroms.
The non-zeolitic molecular sieve prepared using this process is characterized by a three-dimensional microporous framework structure of AlO2, and PO2 tetrahedral oxide units with a unit empirical formula on an anhydrous basis of:
(MxAlyPz)O2 wherein:
"M" represents at least one element, other than aluminum and phosphorous, which is capable of forming an oxide in tetrahedral coordination with AlO2 and PO2 oxide structural units in the crystalline molecular sieve; and
"x", "y", and "z" represent the mole fractions, respectively, of element "M", aluminum, and phosphorus, wherein "x" has a value equal to or greater than zero (0), and "y" and "z" each have a value of at least 0.01.
In a preferred embodiment, metallic element "M" is selected from the group consisting of arsenic, beryllium, boron, chromium, cobalt, gallium, germanium, iron, lithium, magnesium, manganese, silicon, titanium, vanadium, nickel, and zinc, more preferably selected from the group consisting of silicon, magnesium, manganese, zinc, and cobalt; and still more preferably silicon.
While the unit empirical formula represented above is on an anhydrous basis, the non-zeolitic molecular sieve as prepared herein may exist in any state or degree of hydration. It will be clear to one skilled in the art from the present disclosure that the non-zeolitic molecular sieve formed in the reaction mixture may be hydrated to some degree depending on the synthesis material used and on the amount of heat treatment applied to the crystalline molecular sieve. Both hydrated as well as anhydrous non- zeolitic molecular sieves are within the scope ofthe present invention. In preparing the non-zeolitic molecular sieve according to the present invention, an organic templating agent, also known as a structure directing agent, is generally added to the reaction mixture to facilitate crystallization ofthe molecular sieve. Organic templating agents can be selected from those known to be effective in the synthesis of crystalline molecular sieves and crystalline zeolites. U.S. Patent Nos. 4,710,485; 4,440,871; 4,310,440; 4,567,029; 4,686,093; and 4,913,799 include examples of suitable templating agents.
In general the templating agents useful in the present invention contain elements of Group VA ofthe Periodic Table of Elements (CAS), particularly nitrogen, phosphorus, arsenic and antimony, preferably nitrogen or phosphorus and most preferably nitrogen. The templating agents also contain at least one alkyl or aryl group having from 1 to 8 carbon atoms. Particularly preferred nitrogen-containing compounds for use as templating agents are the amines and quaternary ammonium compounds, the latter being represented generally by the formula P N+ wherein each R is an alkyl or aryl group containing from 1 to 8 carbon atoms. Polymeric quaternary ammonium salts such as [(Ci4H32N2)(OH)2]x wherein "x" has a value of at least 2 are also suitably employed. Both mono-, di- and triamines are advantageously utilized, either alone or in combination with a quaternary ammonium compound or other templating compound. Mixtures of two or more templating agents can either produce mixtures ofthe desired non-zeolitic molecular sieves or the more strongly directing templating species may control the course ofthe reaction with the other templating species serving primarily to establish the pH conditions ofthe reaction gel. Representative templating agents include tetramethyiammonium, tetraethylamonium, tetrapropylammonium or tetrabutylammonium ions; di-n-propylamine; di-isopropylamine; tripropylamine; triethylamine, triethanolamine, piperidine; cyclohexylamine; 2-methylethanolamine; choline; NiN-dimethylbenzylamine; N|N- dimethylethanolamine; choline; NiN-dimethylpiperazine; l,4-diazabicyclo(2,2,2,)octane; N-methyldiethanolamine, N-methylethanolamine; N-methylpiperidine; 3-methylpiperidine; N-methylcyclohexylamine; 3-methylpyridine; 4-methylpyridine; quinuclidine; N]N- dimethyl- l,4-diazabicyclo(2,2,2) octane ion; di-n-butylamine, neopentylamine; di-n- pentylamine; isopropylamine; t-butylamine; ethylenediamine; pyrolidine; and 2- imidazolidone. Not every templating agent will direct the formation of every species of non-zeolitic molecular sieve, i.e., a single templating agent can, with proper manipulation ofthe reaction conditions, direct the formation of several non-zeolitic molecular sieve compositions, and a given non-zeolitic molecular sieve composition can be produced using several different templating agents. In the preparation ofthe non-zeolitic molecular sieve, phosphoric acid is the preferred source of phosphorous. Organic phosphates and a crystalline aluminophosphate can also be employed as a source of phosphorous. Silica sol or fumed silica are preferred sources of silicon. Silica gel, alkoxides of silicon, and reactive solid amoφhous precipitated silica are also suitable. Preferred sources ofthe optional element "M" include any elemental or compound form of element "M" which will form oxide units in tetrahedral coordination in the molecular sieve without being detrimental to the integrity ofthe molecular sieve. Salts of element "M", including halogen, nitrate, sulfate, oxide, sulfides, acetate and oxalate salts are examples of active sources of element "M" which may be used in the present process.
The reaction mixture from which the NZMS is made, expressed in terms of molar oxide ratios on an anhydrous basis, has the following preferred bulk composition: aR:(MxAlyPI)O2:bH2O where "R" is a template, "a" has a value great enough to constitute an effective concentration of "R" and is within the range of from greater than zero (0) to about 3; "b" has a value of from zero to 500; "x", "y", and "z" represent the mole fractions, respectively, of element "M", aluminum, and phosphorus wherein "x" has a value equal to or greater than zero (0), and "y" and "z" each have a value of at least 0.01, and wherein "M" represents at least one element, other than aluminum and phosphorous, which is capable of forming an oxide in tetrahedral coordination with AlO2 and PO2.
A preferred synthesis method of this invention comprises:
a) combining an active source of phosphorous and a particulate hydrated alumina to form a reaction mixture, the particulate hydrated alumina having an average particle size of less than about 40μ, a particle density of less than about 1.0 g/cm3 and an alkali content of less than 0.12 wt%, thereafter adding to the reaction mixture an organic templating agent and optionally active source(s) of one or more additional elements "M" capable of forming oxides in tetrahedral coordination with AlO2 and PO units; b) heating the complete reaction mixture at autogenous pressure to a temperature in the range of from 120°C to 220°C until crystals ofthe molecular sieve are formed; and
c) recovering the crystals. A more preferred method for according to the instant process comprises:
a) preparing an aqueous reaction mixture containing phosphoric acid, a reactive source of SiO2, an organic templating agent and a particulate hydrated alumina having an average particle size of less than 40μ, a particle density of less than about 1.0 g cm3 and an alkali content of less than 0.12 wt%, said reaction mixture having a composition expressed in terms of mole ratios of:
aR : Al2O3 : (0.9-1.2)P2O5 : (0.1-4.0)SiO2 : bH2O
wherein R is an organic templating agent; "a" has a value large enough to constitute an effective amount of R and preferably has a value such that there are from 0.20 to 2 moles of R per mole of aluminum oxide; "b" has a value such that there are zero (0) to 100 moles of H2O per mole of aluminum oxide; said reaction mixture having been formed by combining the alumina and phosphorous sources in the substantial absence ofthe silicon source and thereafter combining the resulting mixture with the silicon source and the organic templating agent to form the complete reaction mixture;
b) heating the reaction mixture at autogenous pressure to a temperature in the range of from 120°C. to 220°C. until crystals ofthe non-zeolitic molecular sieve are formed; and
c) recovering said crystals.
-io- In the preferred synthesis procedure for MAPO-5, MAPO-11, MAPO-14, MAPO-34 and CoAPO-14 molecular sieves, a reaction mixture is prepared having a composition expressed in terms of molar oxide ratios as follows: aR : (MxAlyPz)θ2:bH2O
wherein "R" is a templating agent; "a" has a value great enough to constitute an effective concentration of "R" and is within the range of greater than 0 to 6; "b" has a value of zero to 500, preferably 2 to 30; "M" represents magnesium or cobalt; "x", "y" and "z" represent the mole fractions, respectively, of "M", aluminum and phosphorous in the (MxAlyPz)θ2 constituent, and each has a value of at least 0.01. In the preparation ofthe reaction mixture in which the crystalline NZMS is formed, water is added to facilitate crystallization and subsequent processing. In one embodiment, the molar ratio of water to alumina in the reaction mixture is in the range of from about zero to about 8, preferably from about 1 to about 6. In this embodiment, sufficient water is added to the reaction mixture prior to crystallization so that the reaction mixture may be adequately blended and may be formed into self-supporting particles. Beyond that amount of water, no additional water is required for crystallization. This method is described in detail in U.S. Patent Number 5,514,362.
In a separate embodiment, an aqueous reaction mixture is prepared containing active sources ofthe NZMS, including sources of alumina, phosphorous and optionally an element other than aluminum and phosphorous to be incorporated into the crystalline molecular sieve. Frequently, a templating agent will also be present. The amount of water added to the reaction mixture in this embodiment is generally less than about 500 moles of water per mole of alumina, preferably from about 8 to about 100, more preferably from about 10 to about 50, moles of water per mole of alumina. At the start of reaction the pH ofthe reaction mixture may be adjusted as required for the synthesis ofthe desired molecular sieve. As an example, the reaction mixture from which siiicoaluminophosphates are prepared will typically have an initial pH in the range of about 4.0 to about 8.5. Crystallization ofthe molecular sieve is conducted at hydrothermai conditions under pressure and usually in an autoclave so that the reaction mixture is subject to autogenous pressure and preferably with stirring. Following crystallization, the reaction mixture containing the crystallized molecular sieve is filtered if sufficient free liquid water is present and the recovered crystals are washed, for example, with water, and then dried, such as by heating at from 25°C to 150°C at atmospheric pressure. Preferably any supematant liquid above the crystals is removed prior to the initial filtering ofthe crystals.
The molecular sieve prepared by the present method is beneficially subjected to thermal treatment to remove the organic templating agent. This thermal treatment is generally performed by heating at a temperature of 300°C to 800°C for at least 1 minute and generally not longer than 20 hours. While subatmospheric pressure can be employed for the thermal treatment, atmospheric pressure is desired for reasons of convenience. The thermally treated product is particularly useful in the catalysis of certain hydrocarbon conversion reactions.
The non-zeolitic molecular sieve can be used in intimate combination with hydrogenating components, such as tungsten, vanadium, molybdenum, rhenium, nickel, cobalt, chromium, manganese, or a noble metal, such as palladium, platinum, rhodium, rhenium, iridium or mixtures thereof, for those applications in which a hydrogenation- dehydrogenation function is desired. Group VIII metals selected from the group consisting of at least one of platinum and palladium are preferred. The amount of metal ranges from about 0.01% to about 10% by weight ofthe molecular sieve, preferably from about 0.2 to about 5 % by weight ofthe molecular sieve.
Hydrogen, ammonium, and the metal components can be exchanged into the molecular sieve. The molecular sieve can also be impregnated with the metals, or the metals can be physically intimately admixed with the molecular sieve using standard methods known to the art. Alternatively, the metals can be occluded in the crystal lattice by having the desired metals present as ions in the reaction mixture from which the molecular sieve is prepared. The techniques of introducing catalytically active metals to a molecular sieve are disclosed in the literature, and pre-existing metal incorporation techniques and treatment ofthe molecular sieve to form an active catalyst such as ion exchange, impregnation or occlusion during sieve preparation are suitable for use in the present process. Such techniques are disclosed in U.S. Patent Nos. 3,236,761; 3,226,339; 3,236,762; 3,620,960, 3,373,109, 4,202,996; 4,440,781 and 4,710,485.
The term "metal" or "active metal" as used herein means one or more metals in the elemental state or in some form such as sulfide, oxide and mixtures thereof. Regardless of the state in which the metallic component actually exists, the concentrations are computed as if they existed in the elemental state.
Following addition ofthe metals, the molecular sieve may be calcined in air or inert gas at temperatures ranging from about 200°C. to 700°C. for periods of time ranging from 1 to 48 hours, or more, to produce a catalytically active product especially useful in hydrocarbon conversion processes.
The non-zeolitic molecular sieve may be used as a catalyst, without additional forming, when the shaped particles, formed from the reaction mixture described hereinbefore, are of a size and shape desired for the ultimate catalyst. Alternatively, the molecular sieve can be composited with one or more of materials resistant to the temperatures and other conditions employed in organic conversion processes, using techniques such as spray drying, extrusion, and the like. Such matrix materials include active and inactive materials and synthetic or naturally occurring zeolites as well as inorganic materials such as silica, clays and metal oxides such as alumina, magnesia, and titania. Examples of zeolites include synthetic and natural faujasites (e.g., X and Y), erionites, mordenites, and those ofthe ZSM series, e.g., ZSM-5, etc. The combination of zeolites can also be composited in a porous inorganic matrix. The inorganic materials may occur naturally or may be in the form of gelatinous precipitates, sols, or gels, including mixtures of silica and metal oxides. Use of an active material in conjunction with the synthetic molecular sieve, i.e., combined with it, tends to improve the conversion and selectivity ofthe catalyst in certain organic conversion processes. Inactive materials can suitably serve as diluents to control the amount of conversion in a given process so that products can be obtained economically without using other means for controlling the rate of reaction. Frequently, molecular sieve materials have been incoφorated into naturally occurring clays, e.g., bentonite and kaolin. These materials, i.e., clays, oxides, etc., function, in part, as binders for the catalyst. It is desirable to provide a catalyst having good crush strength, because in petroleum refining the catalyst is often subjected to rough handling. This tends to break the catalyst down into powders which cause problems in processing. Naturally occurring clays which can be composited with the new crystal include the montmorillonite and kaolin families which include the subbentonites, and the kaolins commonly known as Dixie, McNamee, Georgia, and Florida clays or others in which the main mineral constituent is halloysite, kaolinite, dickite, nacite, or an auxite. Such clays can be used in the raw state as originally mined or initially subjected to calcination, acid treatment, or chemical modification. Binders useful for compositing with the present crystal also include inorganic oxides, notably alumina or silica. In addition to the foregoing materials, the non-zeolitic molecular sieve produced can be composited with a porous matrix material such as aluminum phosphate, silica- alumina, silica-magnesia, silica-zirconia, silica-thoria, silica-beryllia, silica-titania as well as ternary compositions such as silica-alumina-thoria, silica-alumina-zirconia, silica-alumina- magnesia, and silica-magnesia-zirconia. The relative proportions of finely divided crystalline non-zeolitic molecular sieve material and inorganic oxide gel matrix vary widely, with the crystal content ranging from 1 to 90% by weight, and more particularly when the composite is prepared in the form of beads, in the range of 2 to 80 weight percent ofthe composite.
Non-zeolitic molecular sieves prepared in the present process are useful for a variety of organic, e.g., hydrocarbon compound conversion processes. Hydrocarbon conversion reactions are chemical and catalytic processes in which carbon containing compounds are changed to different carbon containing compounds. Examples of hydrocarbon conversion reactions include catalytic cracking, hydrocracking, dewaxing, and olefin and aromatics formation reactions, including formation from oxygenates. The catalysts are useful in other petroleum refining and hydrocarbon conversion reactions such as isomerizing and hydroisomerizing paraffins and olefins, polymerizing and oligomerizing olefinic or acetylinic compounds such as isobutylene and pentene- 1 , reforming, alkylating, isomerizing polyalkylsubstituted aromatics (e.g. meta xylene), and disproportionating aromatics (e.g. toluene) to provide mixture of benzene, xylenes and higher methylbenzenes.
The molecular sieve prepared in the present process can be used in a process to dewax hydrocarbonaceous feeds. The catalytic dewaxing conditions are dependent in large measure on the feed used and upon the desired pour point. Generally, the temperature will be between about 200° C. and about 475° C, preferably between about 250° C. and about 450° C. The pressure is typically between about 200 psig and 3000 psig. The liquid space velocity (LHSV) preferably will be from 0.1 to 20, preferably between about 0.2 and about 10. Hydrogen is preferably 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), preferably about 1000 to about 20,000 SCF/bbl. Generally, hydrogen will be separated from the product and recycled to the reaction zone.
It has been found that the present dewaxing process provides selective conversion of waxy n-paraffins to non-waxy products of higher molecular weight when compared to products obtained using the prior art zeolitic catalyst. During the processing, the n- paraffins and the slightly branched paraffins undergo some cracking or hydrocracking to form liquid range materials which contribute to a low viscosity product. The degree of cracking which occurs is, however, limited so that the gas yield is reduced, thereby preserving the economic value ofthe feedstock. At the same time, a measurement of isomerization takes place, so that not only is the pour point reduced by reason ofthe cracking reactions described above, but in addition the n-paraffins become isomerized to iso-paraffins to form liquid range materials which contribute to a low viscosity, low pour point product.
The dewaxing process may be used to dewax a variety of feedstocks ranging from relatively light distillate fractions up to high boiling stocks such as whole crude petroleum, reduced crudes, vacuum tower residua, cycle oils, synthetic crudes (e.g., shale oils, tars and oils, etc.), gas oils, vacuum gas oils, foot oils, and other heavy oils. The feedstock will normally be a Cιo+ feedstock generally boiling above about 350° F. containing paraffins, olefins, naphthenes, aromatics, and heterocyclic compounds and with a substantial proportion of higher molecular weight n-paraffins and slightly branched paraffins which contribute to the waxy nature ofthe feedstock since lighter oils will usually be free of significant quantities of waxy components. The process is particularly useful with waxy distillate stocks such as middle distillate stocks including gas oils, kerosenes, and jet fuels, lubricating oil stocks, heating oils and other distillation fractions whose pour point and viscosity need to be maintained within certain specification limits. Lubricating oil stocks will generally boil above 230° C. (450° F.), more usually above 315° C. (600° F.). Hydroprocessed stocks which include stocks which have been hydrotreated to lower metals, nitrogen and sulfur levels and/or hydrocracked, are a convenient source of stocks of this kind and also of other distillate fractions since they normally contain significant amounts of waxy n-paraffins.
While the process herein can be practiced with utility when the feed contains organic nitrogen (nitrogen-containing impurities), it is preferred that the organic nitrogen content ofthe feed be less than 50, more preferably less than 10, ppmw.
The NZMS catalyst may be used to isomerize a waxy feedstock. The waxy feedstock preferably contains greater than about 50% wax, more preferably greater than about 90% wax. However, a highly paraffinic feed having a high pour point, generally above about 0° C, more usually above about 10° C, but containing less than 50% wax is also suitable for use in the process ofthe invention. Such a feed should preferably contain greater than about 70% paraffinic carbon, more preferably greater than about 80% paraffinic carbon, most preferably greater than about 90% paraffinic carbon.
Exemplary additional suitable feeds for use in the process ofthe invention include waxy distillate stocks such as gas oils, lubricating oil stocks, synthetic oils such as those by Fischer-Tropsch synthesis, high pour point polyalphaolefins, foots oils, synthetic waxes such as normal alphaolefin waxes, slack waxes, deoiled waxes and microcrystalline waxes. Foots oil is prepared by separating oil from the wax. The isolated oil is referred to as foots oil.
Slack wax can be obtained from either a hydrocracked lube oil or a solvent refined lube oil. Hydrocracking is preferred because that process can also reduce the nitrogen content to low values. With slack wax derived from solvent refined oils, deoiling can be used to reduce the nitrogen content. Optionally, hydrotreating ofthe slack wax can be carried out to lower the nitrogen content thereof. Slack waxes possess a very high viscosity index, normally in the range of from 140 to 200, depending on the oil content and the starting material from which the wax has been prepared. Slack waxes are therefore eminently suitable for the preparation of lubricating oils having very high viscosity indices, i.e., from about 120 to 180.
In the dewaxing process using the catalyst ofthe present invention, the pour point ofthe dewaxed product is lower than the pour point ofthe feed to the dewaxing process. For oils of commercial interest, the pour point ofthe oil is generally below about 10°C, and often below 0°C. Indeed, with the proper choice of dewaxing conditions and feedstock, a pour point below -24° C. (generally between -24° C. and -63° C.) can be achieved. While the viscosity index ofthe dewaxed oil is not critical to the dewaxing process, it is a feature ofthe dewaxing process using the present catalyst that the viscosity index ofthe feedstock is not adversely affected, and is indeed often improved, in the dewaxing process. This is in contrast to conventional dewaxing processes using zeolite catalysts, in which the viscosity index is frequently reduced during dewaxing. The viscosity index ofthe dewaxed oil will generally be above 90. Depending on the dewaxing conditions and the feeds used for the dewaxing process, a viscosity index between 125 and 180 can be achieved.
When used in the dewaxing process, the non-zeolitic molecular sieve is employed in admixture with at least one group VIII metal as, for example, the noble metals such as platinum and palladium, and optionally other catalytically active metals such as nickel, tungsten, molybdenum, cobalt, vanadium, zinc, etc. The amount of metal ranges from about 0.01% to 10% and preferably 0.2 to 5% by weight ofthe molecular sieve.
The Group VIII metal utilized in the process of this invention can mean one or more ofthe metals in its elemental state or in some form such as the sulfide or oxide and mixtures thereof. As is customary in the art of catalysis, when referring to the active metal or metals, it is intended to encompass the existence of such metal in the elementary state or in some form such as the oxide or sulfide as mentioned above, and regardless of the state in which the metallic component actually exists, the concentrations are computed as if they existed in the elemental state.
The NZSM can be used in a process to prepare lubricating oils. The process comprises (a) hydrocracking in a hydrocracking zone a hydrocarbonaceous feedstock to obtain an effluent comprising a hydrocracked oil, and (b) catalytically dewaxing in a catalytic dewaxing zone the hydrocracked oil of step (a) with a catalyst comprising a non- zeolitic molecular sieve and a Group VIII metal, preferably platinum or palladium.
Another embodiment of this process includes an additional step of stabilizing said dewaxed hydrocrackate by catalytic hydrofinishing.
The hydrocarbonaceous feeds from which lube oils are made usually contain aromatic compounds as well as normal and branched paraffins of very long chain lengths. The feeds usually boil in the gas oil range. Preferred feedstocks are vacuum gas oils with normal boiling ranges in the range of 350° C. to 600° C, and deasphalted residual oils having normal boiling ranges from about 480° C. to 650° C. Reduced topped crude oils, shale oils, liquefied coal, coke distillates flash or thermally cracked oils, atmospheric residua, and other heavy oils can also be used. The first step in the processing scheme is hydrocracking. In commercial operations, hydrocracking can take place as a single-step in the process, or as a multistep process using initial denitrification or desulfurization steps, all of which are well known.
A typical hydrocracking process is described, for example, in U.S. Patent No. 5,158,665, the entire disclosure of which is incoφorated herein by reference. It may further be desired to hydrofinish the dewaxed oil in a mild hydrogenation process to produce more stable lubrication oils. A description of a typical hydrofinishing process and catalyst which is useful in the present process is also taught in U.S. Patent No. 5,158,665.
The following examples are provided to illustrate the invention and are not intended to be limiting thereof:
EXAMPLES Example 1 SAPO-11 was prepared as follows: a reaction mixture was prepared by combining 502 grams of 86% H3PO4 with 320 grams of deionized ice in a Teflon beaker in a cold water bath. To the reaction mixture were slowly added 129 grams of Al(OH)3 (52 wt% AI2O3) with 577 grams of cold deionized water while simultaneously mixing with a stirrer and grinding with a Polytron. The Al(OH)3, F-2000: R254-30 alumina hydroxy carbonate supplied by Reheis Inc. (New Jersey), had an average particle diameter of 9.4 microns (by Malvern particle size analysis). The sodium content ofthe Al(OH)3 was about 0.08 wt%. The particle density ofthe Al(OH)3 was 0.57 g/cm3.
98 grams of di-n-propylamine were then added to the reaction mixture, followed by another 300 grams of Al(OH)3 and 253 grams of cold water with mixing grinding. Another 98 grams of di-n-propylamine were then added along with 64 grams of fumed silica (Cabosil M-5) with mixing/grinding. The mixture had the following composition, expressed in molar ratio of oxides:
0.9 Pr2NH : 0.5 SiO2 : Al2O3 : P2O5 : 36 H2O The mixture was placed in a Teflon bottle in a stainless steel pressure vessel and heated for 2 days at 190°C. at autogenous pressure with stirring. The supernatant liquid was removed and the product filtered, washed with water, dried overnight at 120°C. in a vacuum oven, and calcined in air at 593°C. for 8 hours. X-ray diffraction analysis identified the product as SAPO-11. The average crystallite size by SEM was less than 0.5 microns. The calcined sieve had the following anhydrous molar composition:
0.48SiO2 : Al2O3 : 0.92 P2O5 The sodium content ofthe sieve was about 300 ppm. Example 2
The sieve of Example 1 was impregnated with 0.5 wt% platinum and tested in a continuous-flow high-pressure pilot plant for lowering the pour point of a hydrocracked heavy neutral oil (Table I). Run conditions were 2.3 hr'1 WHSV (weight hourly space velocity), 1950 psi (13.5 MPa) total pressure, and 8 MSCF/bbl once-through H2 (1425 std m3 H/m3 oil). Results are shown in Table II.
Example 3 80 grams ofthe 4.7 micron Reheis Al(OH)3 from Example 1 were placed in a small Baker-Perkins mixer. To this were added 8 grams of water and 89.8 grams of 86% H3PO4, followed by 9.6 grams of filmed silica (Cabosil M-5) and 14 grams of peptized and neutralized Catapal alumina (40 wt% Al2O3, 60 wt% H2O), the latter to serve as a binder and to facilitate extrusion. After about 2 hours of mixing, 28.8 grams of a 3/1 template mixture of di-n-propylamine and di-isopropylamine were added with mixing. The mix was partially air-dried in a hood and then extruded through a 1/12-inch die. The extrudate was placed in a Teflon bottle in a stainless steel pressure vessel and crystallized at 180°C. and autogenous pressure for 2 days. Synthesis molar ratios, expressed as oxides, were as follows:
P2O5/Al2O3 = 0.84 template mixture/P2O5 = 0.73
Figure imgf000021_0001
The product was washed with water, dried overnight in a vacuum oven at 120°C, and then calcined in air at 593°C for 6 hours. X-ray diffraction analysis showed the product to be SAPO-11.
Example 4 The catalyst of Example 3 was impregnated with 0.5 wt% Pt and tested for lowering the pour point ofthe waxy hydrocracked heavy neutral feedstock of Table I.
Run conditions were 2.3 hr"1 WHSV, 1950 psi (13.5 MPa) total pressure, and 8 MSCF/bbl once-through H2 (1425 std 3 H2/m3 oil). Results are shown in Table III. Example 5 502 grams of 86% H3PO4 were placed in a stainless steel bucket'in an ice bath. To the bucket were added 120 grams of deionized ice and 600 grams of cold water. To this were slowly added 129 grams of Al(OH)3 (Reheis F-2000: R254-27 Al(OH)3 with a sodium content of 0.04 wt%) along with 577 grams of cold deionized water while simultaneously mixing with a stirrer and grinding with a Polytron. Then 98 grams of di-n-propylamine were added, followed by another 300 grams of Al(OH)3 and 253 grams of cold water with mixing/grinding. Another 98 grams of di-n-propylamine were then added along with 64 grams of fumed silica with mixing/grinding. The mixture had the following composition, expressed in molar ratio of oxides:
0.9 Pr2NH : 0.5 SiO2 : Al2O3 : P2Os : 45 H2O The maximum viscosity during the mix was 480 cp (measured at 20°C), which was also the final viscosity. The mixture was placed in a stainless steel container and crystallized in a pressure vessel at 190°C for two days at autogenous pressure with stirring. The supematant liquid was removed and the product filtered, washed with water, dried overnight at 120°C in a vacuum oven, and calcined in air at 593°C for six hours. X-ray diffraction analysis identified the product as SAPO- 1 1. The average crystallite size by SEM was less than 0.5 microns. The calcined sieve had the following anhydrous molar composition: 0.48 SiO2 : AI2O3 : 0.89 P2O5
Example 6 The sieve of Example 5 was mixed with 15 wt % (volatiles free) peptized Catapal alumina and extruded through a 1/16-inch die. The extrudate was dried in an oven at 66°C for one hour, 93°C for one hour, and 121°C for three hours, and then calcined in flowing air at 454°C for four hours. The extrudate was then impregnated with 0.4 wt % platinum using an aqueous solution of Pt(NH3)4Cl2 The extrudate was dried at 66°C for three hours, and then calcined in flowing air at 288°C for four hours.
The catalyst was crushed to 24-42 mesh and tested for lowering the pour point of the feed of Table 1. Run conditions were 1.6 hr"1 LHSV (liquid hourly space velocity), 1950 psi (13.5 MPa) total pressure, and 8 MSCF/bbl once-through H2 (1425 std m3
H2/m3 oil). Results are shown in Table IV. The following example illustrates the effect of using a hydrated alumina having a particle size and particle density outside the range ofthe alumina source'of the present invention.
Comparative Example 1 SAPO- 11 was prepared similar to Example 3 except that the Reheis Al(OH)3 was substituted by 56 grams of a hydrated aluminum oxide (pseudo-boehmite, 73 wt% Al2O3, 37 wt% H2O) containing 70 ppm sodium. The average particle diameter ofthe hydrated aluminum oxide was 134 microns, and the particle density approximately 1.3 g/cm3. The catalyst was impregnated with Pt and tested for dewaxing as in Example 4. At a catalyst temperature of 720°F (382°C), the product pour point was -3°C, showing less pour point reduction than a catalyst of this invention at the same reactor temperature.
The following example illustrates the effect of using a hydrated alumina having an alkali content outside the range ofthe alumina source ofthe present invention.
Comparative Example 2 SAPO-11 was prepared as in Example 5 with the exception that the Al(OH)3 contained a sodium level of 0.14 wt %. The calcined sieve had the same composition as the sieve of Example 5 but with a sodium content of 530 ppm.
An extrudate catalyst containing 0.4 wt % Pt was then prepared as in Example 6 using this sieve. The catalyst was then used to lower the pour point ofthe feed of Table 1 at the same conditions as listed in Example 6. The results, given in Table IV, show that this catalyst was over 40°F less active than the catalyst of Example 6.
The following example illustrates the effect of using a hydrated alumina having an alkali content outside the range ofthe alumina source ofthe present invention, and illustrates the effect on catalyst performance of removing alkali from the finished non- zeolitic molecular sieve.
Comparative Example 3 SAPO-11 was prepared as in Example 1 with the exception that the Al(OH)3 (Reheis F-2000 alumina hydroxy carbonate having the same physical properties as that used in Example 1, but with higher sodium content) contained a sodium level of 0.25 wt %. The calcined sieve had the following anhydrous molar composition:
0.44 SiO : Al2O3 : 0.93 P2O5 The sodium content was 710 ppm. The sieve was then divided into two portions. The first was impregnated with 0.5 wt % Pt. The other portion was first exchanged with an aqueous, ammonium acetate solution to lower the sodium content ofthe sieve to 240 ppm, and then impregnated with 0.5 wt % Pt. Both sieves were tested for lowering the pour point of a heavy neutral oil similar to that of Table 1. Run conditions were 2.3 WHSV, 1950 psi (13.5 MPa) total pressure, and 8 MSCF/bbl once-through H2 (1425 std m3 H2/m3 oil). The NR exchanged sieve was 5 to 10 °F less active than the starting sieve, showing that exchange ofthe sieve to remove sodium after synthesis is not effective in improving activity compared to starting with a low sodium AJ(OH)3.
The following example illustrates that using a hydrated alumina having a particle density outside the range ofthe present invention adversely affects the viscosity ofthe reaction mixture.
Comparative Example 4 502 grams of 86% H3PO4 were added to a stainless steel bucket cooled in an ice bath. 240 grams of deionized ice were then added with stirring. 105 grams of Catapal alumina (73 wt% Al2O3, 27 wt% H2O), and 791 grams of deionized ice were slowly added with stirring and grinding over a 90-minute time period. The Catapal as used had a particle density of approximately 1.3 g/cm3. At that point, the viscosity ofthe mix, measured at 16°C, had risen to 29,000 cp. 98 grams of di-n-propylamine were then added. 192 more grams of alumina were added (to bring the Al/P mole ratio to 0.97) along with 250 grams of ice. The mixture had the following composition, expressed in molar ratio of oxides:
0.9 Pr2NH : 0.5 SiO2 : Al2O3 : P2O$ : 37 H2O The viscosity ofthe mix was 15,000 cp. The high viscosity of this preparation makes synthesis at a large scale difficult due to problems in mixing.
Comparative Example 5 SAPO-11 was prepared according to Example 1 of U.S. Patent No. 5,246,566. The alumina source was aluminum isopropoxide (Al[OC3H7]3), and the sodium content of the resulting SAPO- 11 was found to be approximately 40 ppm. This comparative example shows that SAPO-1 1 made using a known source of alumina had a sodium level below that ofthe present non-zeolitic molecular sieve.
Figure imgf000025_0001
Table II -
Dewaxing Heavy Neutral at 2.3 WHSV and 1950 psi (13.5 MPa)
Rxn Temperature, °F. (°C) 690°F (366°C) 697°F (369°C)
Yield
Total Lube Yield, LV% 90.1 90.4
Yield of 700 °F+ (371°C+) 94.1 92.5 product, wt %
Product Properties
Pour Point, °C -9 -13
Cloud Point, °C -6 -11
Viscosity, cSt
@ 40 °C 125.3 121.9
@ 100 °C 12.90 12.72
Viscosity Index 95 96
Sim. Dist., LV% op oς op oς
St/5 779/841 415/449 762/837 406/447
10/30 865/915 463/491 862/914 461/490
50 950 510 950 510
70/90 987/1038 531/559 986/1038 530/559
95/EP 1067/1138 575/614 1066/1 138 574/614
Table III -
Dewaxing Heavy Neutral at 2.3 WHSV and 1950 psi (13.5 MPa)
Reactor temperature, °F (°C) 720 (382) 728 (387)
Yield
Total Lube Yield, LV % 88.8 87.6
Yield of 700 °F+ (371°C+) 85.4 84.0 product, wt %
Product Properties
Pour Point, °C -14 -18
Cloud Point, °C -10 -13
Viscosity, cSt
@40 °C 1 10.0 106.5
@100 °C 1 1.73 1 1.53
Viscosity Index 94 95
Sim. Dist., LV %, op oς op oς
St/5 638/764 337/407 532/759 278/404
10/30 813/897 434/481 813/896 434/480
50 939 504 938 503
70/90 979/1035 526/557 978/1033 526/556
95/EP 1069/1 142 576/617 1068/1 142 576/617
Figure imgf000028_0001

Claims

I CLAIM:
1. A process for preparing a molecular sieve comprising maintaining a reaction mixture containing an active source of phosphorous, a particulate hydrated alumina and optionally active source(s) of one or more additional elements "M", capable of forming oxides in tetrahedral coordination with AlO2 and PO2 units, under crystallization conditions until crystals of a non-zeolitic molecular sieve form, the particulate hydrated alumina having an average particle size of less than about 40μ, a particle density of less than about 1.0 g/cm3 and an alkali content of less than 0.12 wt%.
2. The process according to Claim 1 wherein "M" is selected from silicon, magnesium, manganese, zinc, and cobalt
3 The process according to Claim 2 wherein "M" is silicon.
4. The process according to Claim 3 wherein the molecular sieve is SAPO-1 1
5. The process according to Claim 1 wherein the reaction mixture further contains a templating agent selected from di-n-propylamine, di-isopropylamine or mixtures thereof.
6. The process according to Claim 1 wherein the reaction mixture further comprises at least one reactive source of SiO2, the reaction mixture having a composition expressed in terms of mole ratios of. aR:Al2O3 : (0.9-1.2)P2O5 (0 1-4 0)SiO2 bH2O wherein "R" is an organic templating agent; "a" has a value large enough to constitute an effective amount of "R"; "b" has a value such that there are 8 to 100 moles of H2O per mole of alumina.
7. The process according to Claim 1 wherein the reaction mixture further comprises at least one reactive source of SiO2, the reaction mixture having a composition expressed in terms of mole ratios of: aR:Al2O3 : (0.9-1.2)P2O5 : (0.1-4 0)SiO2. bH2O wherein "R" is an organic templating agent; "a" has a value large enough to constitute an effective amount of "R"; "b" has a value such that there are zero (0) to about 8 moles of H O per mole of alumina.
8. A process for preparing a molecular sieve comprising combining an active source of phosphorous, a particulate hydrated alumina and optionally active source(s) of one or more additional elements "M" capable of forming oxides in tetrahedral coordination with AlO2 and PO2 units to form a reaction mixture, the particulate hydrated alumina having an average particle size of less than about 40μ, a particle density of less than about 1.0 g/cm3 and an alkali content in the range from about 0.01 wt% to about 0.12 wt%, and heating the reaction mixture to a temperature in the range of from 120°C to 220°C until crystals of the molecular sieve are formed.
9. The process according to Claim 8 wherein the reaction mixture has a composition, expressed in terms of molar oxide ratios, of aR:(MxAlyPz)O2:bH2O where "R" is the template, "a" has a value great enough to constitute an effective concentration of "R" and is within the range of from greater than zero (0) to about 3; "b" has a value of from zero to 500; "x", "y", and "z" represent the mole fractions, respectively, of element "M", aluminum, and phosphorus wherein "x" has a value equal to or greater than zero (0), and "y" and "z" each have a value of at least 0.01.
10. The process according to Claim 8 wherein "M" is selected from silicon, magnesium, manganese, zinc, and cobalt.
11. The process according to Claim 8 wherein the sodium content ofthe particulate hydrated alumina is in the range from about 0.01 wt% to about 0.10 wt%.
12. A process for preparing a molecular sieve comprising:
a) preparing an aqueous reaction mixture containing phosphoric acid, a reactive source of SiO , an organic templating agent and a particulate hydrated alumina having an H2O/Al2O3 molar ratio of greater than about 2.6, an average particle size of less than 40μ, and a sodium content of less than 0.12 wt%, said reaction mixture Raving a composition expressed in terms of mole ratios of:
aR:Al2O3 : (0.9-1.2)P2O5 : (0.1-4.0)SiO2 : bH2O
wherein R is an organic templating agent; "a" has a value large enough to constitute an effective amount of R; "b" has a value such that there are zero (0) to 100 moles of H2O per mole of aluminum oxide;
b) heating the reaction mixture to a temperature in the range of from 120°C. to 220°C. until crystals ofthe non-zeolitic molecular sieve are formed; and
c) recovering said crystals.
13. A molecular sieve containing in the range of about 75 to about 500 ppm alkali and having a unit empirical formula on an anhydrous basis of:
(MxAlyP,)O2 wherein "xH, "y", and "z" represent the mole fractions, respectively, of an element "M", aluminum, and phosphorus, wherein "x" has a value equal to or greater than zero (0), and "y" and "z" each have a value of at least 0.01, wherein "M" is an element which is capable of forming oxides in tetrahedral coordination with AlO2 and PO2, and wherein the molecular sieve contains from about 75 to about 500 ppm alkali.
14. The molecular sieve according to Claim 13 which contains in the range of about 75 to about 225 ppm alkali.
15. The molecular sieve according to Claim 14 which is prepared using an alumina source having in the range from about 0.01 wt% to about 0.10 wt% alkali.
16. The molecular sieve according to Claim 13 which is SAPO-1 1 or SM-3.
PCT/US1996/017714 1995-11-07 1996-11-05 Alumina source for non-zeolitic molecular sieves WO1997017291A1 (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
AU75539/96A AU7553996A (en) 1995-11-07 1996-11-05 Alumina source for non-zeolitic molecular sieves
KR1019980703491A KR19990067476A (en) 1995-11-07 1996-11-05 Alumina source for non-zeolitic molecular sieves
EP96937904A EP0859743B2 (en) 1995-11-07 1996-11-05 Alumina source for non-zeolitic molecular sieves
JP51827097A JP4313436B2 (en) 1995-11-07 1996-11-05 Alumina sources for non-zeolitic molecular sieves
DE69604414T DE69604414T3 (en) 1995-11-07 1996-11-05 SOURCE OF SOIL FOR NON-ZEOLITHIC MOLECULAR SCREENS

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US55321195A 1995-11-07 1995-11-07
US08/553,211 1995-11-07
US08/704,055 1996-08-28
US08/704,055 US5741751A (en) 1995-11-07 1996-08-28 Alumina source for non-zeolitic molecular sieves

Publications (1)

Publication Number Publication Date
WO1997017291A1 true WO1997017291A1 (en) 1997-05-15

Family

ID=27070285

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1996/017714 WO1997017291A1 (en) 1995-11-07 1996-11-05 Alumina source for non-zeolitic molecular sieves

Country Status (8)

Country Link
US (1) US5942104A (en)
EP (1) EP0859743B2 (en)
JP (1) JP4313436B2 (en)
KR (1) KR19990067476A (en)
CN (1) CN1087272C (en)
AU (1) AU7553996A (en)
DE (1) DE69604414T3 (en)
WO (1) WO1997017291A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9492818B2 (en) 2009-06-12 2016-11-15 Albemarle Europe Sprl SAPO molecular sieve catalysts and their preparation and uses

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0962469A1 (en) 1998-06-05 1999-12-08 Fina Research S.A. Titanated chromium catalyst supported on silica-aluminophosphate
DE10022369A1 (en) * 2000-05-08 2001-11-15 Bayer Ag Process for the preparation of piperidines
US6521562B1 (en) * 2000-09-28 2003-02-18 Exxonmobil Chemical Patents, Inc. Preparation of molecular sieve catalysts micro-filtration
CN1248994C (en) * 2001-07-02 2006-04-05 埃克森美孚化学专利公司 Inhibiting catalyst coke formation in the manufacture of an olefin
US7271123B2 (en) * 2002-03-20 2007-09-18 Exxonmobil Chemical Patents Inc. Molecular sieve catalyst composition, its making and use in conversion process
US6872680B2 (en) * 2002-03-20 2005-03-29 Exxonmobil Chemical Patents Inc. Molecular sieve catalyst composition, its making and use in conversion processes
WO2004016574A1 (en) * 2002-08-14 2004-02-26 Exxonmobil Chemical Patents Inc. Process for preparing olefins from oxygenates
US7238846B2 (en) * 2002-08-14 2007-07-03 Exxonmobil Chemical Patents Inc. Conversion process
US7138006B2 (en) * 2003-12-24 2006-11-21 Chevron U.S.A. Inc. Mixed matrix membranes with low silica-to-alumina ratio molecular sieves and methods for making and using the membranes
US20070287871A1 (en) * 2006-03-20 2007-12-13 Eelko Brevoord Silicoaluminophosphate isomerization catalyst
JP5158305B2 (en) * 2006-06-02 2013-03-06 東ソー株式会社 High-purity aluminophosphate zeolite, method for producing the same, and use thereof
US20080166563A1 (en) * 2007-01-04 2008-07-10 Goodrich Corporation Electrothermal heater made from thermally conducting electrically insulating polymer material

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4310440A (en) * 1980-07-07 1982-01-12 Union Carbide Corporation Crystalline metallophosphate compositions
EP0103117A1 (en) * 1982-07-26 1984-03-21 Union Carbide Corporation Crystalline silicoaluminophosphates
EP0132708A2 (en) * 1983-07-15 1985-02-13 Uop Crystalline metal aluminophosphates
US4943424A (en) * 1988-02-12 1990-07-24 Chevron Research Company Synthesis of a crystalline silicoaluminophosphate

Family Cites Families (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5445807A (en) * 1983-09-22 1995-08-29 Aluminum Company Of America Production of aluminum compound
US4673559A (en) * 1983-12-19 1987-06-16 Mobil Oil Corporation Silicoaluminophosphate crystallization using hydrolysis
US5084159A (en) * 1985-06-18 1992-01-28 Union Oil Company Of California Process and catalyst for the dewaxing of shale oil
IN167718B (en) * 1985-06-28 1990-12-08 Chevron Res
US5306480A (en) * 1986-07-16 1994-04-26 Alcan International Limited Alumina hydrates
US5374411A (en) * 1987-08-28 1994-12-20 The Dow Chemical Company Crystalline aluminumphosphate compositions
US4861743A (en) * 1987-11-25 1989-08-29 Uop Process for the production of molecular sieves
US5158665A (en) * 1988-02-12 1992-10-27 Chevron Research And Technology Company Synthesis of a crystalline silicoaluminophosphate
US4877593A (en) * 1988-03-10 1989-10-31 Mobil Oil Company Synthesis of crystalline aluminophosphate composition
US4913796A (en) * 1988-03-10 1990-04-03 Mobil Oil Corp. Novel crystalline silicoaluminophosphate
US5169614A (en) 1988-04-08 1992-12-08 Mobil Oil Corporation Synthesis of crystalline silicoaluminophosphate composition
FR2645141B1 (en) * 1989-03-31 1992-05-29 Elf France PROCESS FOR THE SYNTHESIS OF PRECURSORS OF MOLECULAR SIEVES OF THE SILICOALUMINOPHOSPHATE TYPE, PRECURSORS OBTAINED AND THEIR APPLICATION FOR OBTAINING SAID MOLECULAR SIEVES
GB8926602D0 (en) * 1989-11-24 1990-01-17 Shell Int Research Novel crystalline aluminophosphates and related compounds
EP0464249B1 (en) * 1990-07-05 1994-01-05 VAW Aluminium AG Process for the manufacture of crystalline molecular sieves with large pores
GB9023847D0 (en) * 1990-11-02 1990-12-12 Shell Int Research Novel crystalline aluminophosphates and related compounds
US5230881A (en) * 1991-03-01 1993-07-27 Chevron Research & Technology Co. Methods for preparing substantially pure SAPO-31 silicoaluminophosphate molecular sieve
US5126308A (en) 1991-11-13 1992-06-30 Uop Metal aluminophosphate catalyst for converting methanol to light olefins
US5514362A (en) * 1994-05-03 1996-05-07 Chevron U.S.A. Inc. Preparation of non-zeolitic molecular sieves
US5552132A (en) * 1994-10-28 1996-09-03 Chevron U.S.A. Inc. Preparing a crystalline aluminophosphate composition
US5741751A (en) * 1995-11-07 1998-04-21 Chevron U.S.A. Inc. Alumina source for non-zeolitic molecular sieves

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4310440A (en) * 1980-07-07 1982-01-12 Union Carbide Corporation Crystalline metallophosphate compositions
EP0043562A1 (en) * 1980-07-07 1982-01-13 Union Carbide Corporation Crystalline metallophosphate compositions
EP0103117A1 (en) * 1982-07-26 1984-03-21 Union Carbide Corporation Crystalline silicoaluminophosphates
US4440871A (en) * 1982-07-26 1984-04-03 Union Carbide Corporation Crystalline silicoaluminophosphates
EP0132708A2 (en) * 1983-07-15 1985-02-13 Uop Crystalline metal aluminophosphates
US4567029A (en) * 1983-07-15 1986-01-28 Union Carbide Corporation Crystalline metal aluminophosphates
US4943424A (en) * 1988-02-12 1990-07-24 Chevron Research Company Synthesis of a crystalline silicoaluminophosphate

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9492818B2 (en) 2009-06-12 2016-11-15 Albemarle Europe Sprl SAPO molecular sieve catalysts and their preparation and uses

Also Published As

Publication number Publication date
AU7553996A (en) 1997-05-29
CN1087272C (en) 2002-07-10
JP4313436B2 (en) 2009-08-12
US5942104A (en) 1999-08-24
DE69604414T3 (en) 2004-10-28
EP0859743A1 (en) 1998-08-26
JP2000500109A (en) 2000-01-11
KR19990067476A (en) 1999-08-25
CN1201438A (en) 1998-12-09
DE69604414D1 (en) 1999-10-28
EP0859743B2 (en) 2004-02-25
DE69604414T2 (en) 2000-01-05
EP0859743B1 (en) 1999-09-22

Similar Documents

Publication Publication Date Title
EP0758303B1 (en) Preparation of non-zeolitic molecular sieves
US5158665A (en) Synthesis of a crystalline silicoaluminophosphate
EP0458895B1 (en) Isomerization of waxy lube oils and petroleum waxes using a silicoaluminophosphate molecular sieve catalyst
US5246566A (en) Wax isomerization using catalyst of specific pore geometry
US5208005A (en) Synthesis of a crystalline silicoaluminophosphate
US5741751A (en) Alumina source for non-zeolitic molecular sieves
US8449761B2 (en) Synthesis of a crystalline silicoaluminophosphate
EP0209997B1 (en) Catalytic dewaxing of hydrocarbons using a molecular sieve catalyst
EP0859743B1 (en) Alumina source for non-zeolitic molecular sieves
WO1991002782A1 (en) Process for preparing low pour middle distillates and lube oil using a catalyst containing a silicoaluminophosphate molecular sieve
EP2085360B1 (en) Crystalline silicoaluminophosphate
CA2066656C (en) Wax isomerization using catalyst of specific pore geometry
US6464857B2 (en) Crystalline phosphorus-containing molecular sieves
AU2003204702B2 (en) Preparing a high viscosity index, low branch index dewaxed oil

Legal Events

Date Code Title Description
WWE Wipo information: entry into national phase

Ref document number: 96198125.3

Country of ref document: CN

AK Designated states

Kind code of ref document: A1

Designated state(s): AL AM AT AU AZ BA BB BG BR BY CA CH CN CU CZ DE DK EE ES FI GB GE HU IL IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK TJ TM TR TT UA UG UZ VN AM AZ BY KG KZ MD RU TJ TM

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
WWE Wipo information: entry into national phase

Ref document number: 1996937904

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 1997 518270

Country of ref document: JP

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 1019980703491

Country of ref document: KR

WWP Wipo information: published in national office

Ref document number: 1996937904

Country of ref document: EP

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: CA

WWP Wipo information: published in national office

Ref document number: 1019980703491

Country of ref document: KR

WWG Wipo information: grant in national office

Ref document number: 1996937904

Country of ref document: EP

WWW Wipo information: withdrawn in national office

Ref document number: 1019980703491

Country of ref document: KR