CA1319928C - Catalyst for the oxidation of carbon compounds - Google Patents
Catalyst for the oxidation of carbon compoundsInfo
- Publication number
- CA1319928C CA1319928C CA000571915A CA571915A CA1319928C CA 1319928 C CA1319928 C CA 1319928C CA 000571915 A CA000571915 A CA 000571915A CA 571915 A CA571915 A CA 571915A CA 1319928 C CA1319928 C CA 1319928C
- Authority
- CA
- Canada
- Prior art keywords
- catalyst
- temperature
- activated
- percent
- carbon monoxide
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Fee Related
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/38—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals
- B01J23/40—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of noble metals of the platinum group metals
- B01J23/44—Palladium
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/864—Removing carbon monoxide or hydrocarbons
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8668—Removing organic compounds not provided for in B01D53/8603 - B01D53/8665
Abstract
ABSTRACT OF THE DISCLOSURE
New activated palladium zirconium oxide catalysts are disclosed which are based on amorphous or crystallized alloys, as well as new palladium zirconium oxide precipitation catalysts. The new catalysts are suitable for the complete oxidization of carbon monoxide and hydrocarbons.
New activated palladium zirconium oxide catalysts are disclosed which are based on amorphous or crystallized alloys, as well as new palladium zirconium oxide precipitation catalysts. The new catalysts are suitable for the complete oxidization of carbon monoxide and hydrocarbons.
Description
13~9~28 This invention relate~ to an activated palladium zirconium oxide catalyst as an amorphous or crystalline alloy, a PdZrO2 precipitation catalyst as well as processes for total oxidation of carbon monoxide, aliphatic and aromatic hydrocarbons as well as aliphatic alcohols with the aid of these catalysts. The invention especially relates to the total oxidation of said compounds in oxygen-containin~ gas streams, e.~., waste ~as streams from fossil combustion units.
10It is known to use support-bonded noble metal catalysts for the oxidation of carbon monoxide and hydrocarbonQ [Yung-Fana Yu Yao, J. Catal., 8~, 152-162 (1984)]. The process is disadvantageous in that, apart from the use of very expensive noble metal cataly~ts, which render impractical an economical process on a lar~e scale, the reaction temperatures as a rule are set high.
Therefore, from an energy viewpoint, the process i8 even less favorable relative to economic efficiency and costs.
It is also known to use carbon monoxide ln the presence of amorphous metal strlps havln~ the composition Pd35ær65 as a methanizatlon catalyst for C0 and H2 [Yokohama et al., Chemistry Letters, The Chemical Society of Japan, 195-198, (1983)].
An ob~ect of the inventlon is to develop catalysts which do not exhlbit the above discussed drawbac~s.
Accordingly, one a~pect of the invention provldes a flrst class of new activated catalyst of the general formula Pdx(ZrOz)y, wherein x is a number between 301 and 99, y is the difference between x and 100 and æ is a value between 0.5 and 2.
Another aspect of the invention provides a second class of new PdZrO2 precipitation catalysts with a Pd content between 0.2 and 20 percent by weight, produced by the proce6s of:
(a) impre~nating ZrO2 with a water-soluble palladium salt, (b) drying the mixture, and q~
_ . I . A ~ . .
(c~ reducing the Pd complex with hydrogen.
Preferably the activated catalyst of general formula PdxlZrOz)y, wherein x, y and z are as defined above, has the formula Pd33~ZrO2)6~. The activated catalyst is suitably an amorphous or a crystalline alloy.
Production of amorphous alloys is known in the art. An essential feature is that the elements that form the alloys can be premelted under a protective gas, such as, argon. This prealloy is again melted and the melt is 10 finally cooled at a cooling rate of suitably 103 to 109 C~s, preferably 106 to 109 C/s. With this "chilling process", an amorphous phase of the alloy is formed.
Known processes, listed by way of illustration, include the melt spinning process, the splat cool process, and further processes for production of amorphous powders by melting and spraying of the alloy.
According to the invention, crystalline or crystallized alloys of the above defined composition can also be used. Such alloys can be produced in conventional manner,i.e. by melting the initial materials and then permittlng them to cool. It i8 also possible to convert amorphous alloys back to the crystalline state by heating above the crystallization temperature, generally in a high vacuum.
Depending upon the production process, the alloy can be present as strip, pieces of strip, a~ a molded article from strip or in powder form.
In the unactivated state, the catalyst surface area is generally in the range of 0.01 to 0.1 m2/q.
Before their use as catalysts, these alloys according to the invention must first be activated "in situ" or in an oxygen-containing gas stream. Thus, a partial-to-complete oxidation of the zirconium to zirconium oxides of the formula ZrOz, takes place, and z has the above-mentioned meaning. As a rule, most of the palladium remains oxidatively unchanged in the activation, so that the activated catalyst, as X-ray analysis shows, J .`
.'~ .S~
. . , . ~ . .
~319~28 consists mainly of palladium particles which are in a ZrOz matrix.
The phase "in situl' means that the gas mixture containing the reactants, suitably at a temperature 5 between 150 and 350C, and preferably between 200 and 300C, flows over or through the catalyst. After a period of suitably 2 to 400 hours, but generally of 2 to 100 hours, the alloy reaches its full catalytic activity.
Shorter activation times, of 0.1 to 2 hours, are achieved by activation in an air stream. For mere activation, an oxygen-contalnlng gas mixture alone can be used instead of the gas mixture to be reacted.
The reactant activation can be characterized by measurement of the specific surface, e.~., according to the BET method. Thus, a Pdx(ZrOz)y catalyst, depending on the activation, has a specific surface of suitably 15 to 60 m2/g Another method of characterizing the activation is measurement of the metal surface, on the basis of determlnation of chemisorption. The Pdx~ZrOz)~ catalysts according to the invention have, also depending on the activation, a specific metal surface suitably between 2 and 20 m2/g.
The activated catalysts according to the invention are used for the complete oxidation of carbon monoxide, aliphatic and aromatic hydrocarbons as well as aliphatic alcohols in the gas phase. Especially suitable is the process for the total oxidation of ~aid compounds in wa-~te gas streams of fossil combustion units. In this way,the outstanding property of the catalyst according to the invention, namely, the total oxidation of mixtures of said compounds, is emphasized.
The aliphatic hydrocarbons can be saturated or unsaturated, substituted or unsubstituted. Suitable representatives of this class of compounds are, for example, butane, pentane, pentane, hexane and octane.
Representatives aromatic hydrocarbons are, for example, benzene, toluene, ethylbenzene and xylene. As aliphatic , i3~9928 alcohols there may be mentioned shorter-chain compounds such as methanol, ethanol, propanol and butanol, but preferably methanol.
The catalyst according to the invention is especially suitable for the oxidation of carbon monoxide to carbon dioxide and for the total oxidation of methyl alcohol to carbon dioxide and water.
The reaction temperature, i.e. the temperature which is necessary for total oxidation, depends upon the reactant to be oxidized in the gas stream! but suitably is between room temperature and 350C. For the oxidation of methanol the preferred temperature range is between 50 and 200C. For the oxidation of carbon monoxide the preferred temperature range is between 100 and 200~C.
The pressure conditions during the reaction are generally not critical, and the reaction is suitably performed at a pressure between normal atmospheric pressure and 10 bars, preferably at normal atmospheric pressure.
The gas velocity is ad~usted depending on the reactants. Generally, the gas velocity is in the range of 0.05 to lo N1/min x ~ of catalyst.
As mentioned above, the second class of new catalysts of the invention are PdZrO2 precip~tation catalysts with a Pd content between 0.2 and 20 percent by weight produced by a process comprisin~:
(a) impregnating ZrO2 with a water-soluble palladium salt, (b) drying the mixture, and (c) reducing the Pd complex with hydro~en.
According to this aspect of the invention, these catalysts exhibit a Pd content between 0.2 and 20 percent by wei~ht. Preferably, a catalyst with a Pd content of 1 to S percent by weight is used.
3~ The PdZrO2 precipitation catalyst is preferably produced by impre~natin~ a pulverized zirconium oxide having a surface area of 10 to 60 m2/g with a palladium r f~
. .
1319~28 salt dissolved ~n water, dryin~ the moist mixture and reducing the resultant Pd complex with hydroaen.
Palladium chlorides, such as, palladium II
chloride, or complexed palladium chlorides, such as, ammonium tetrach~oropalladate (II), can be used as the water soluble Pd salt.
The reduction is advantageously performed in the presence of a hydro~en-nitrogen mixture in an H2:N2 ratio of between 10 to 1 and 0.1 to 1 at a temperature of 200 to 600~C. The temperature is especially advantageously controlled 50 that the final reduction temperature is reached only after a gradual increase.
Precipitation catalysts of this type are used according to the invention also for the oxidation of carbon monoxide, and the total oxidation of aliphatic and aromatic hydrocarbons, as well as aliphatic alcohols in the gas phase. The process is especially suitable for the total oxidation of such compounds in waste ~as streams.
The aliphatic hydrocarbons can be saturated or unsaturated, substituted or unsubstituted. Suitable representatives of this class of compounds are, for example, butane, pentane, pentane, hexane and octane.
Representative of aromatic hydrocarbons are, for example, benzene, toluene, ethylbenzene and xylene. As aliphatic alcohols there may be mentioned shorter-chain compounds, such as, methanol, ethanol, propanol and butanol, but preferably methanol.
The catalyst accordin~ to this aspect of the invention is especially suitable for the total oxidation of carbon monoxide to carbon dloxide and for the oxidation of methyl alcohol to carbon dioxide and water.
The reaction temperature, i.e. the temperature which is necessary for total oxidation, depends upon reactants to be oxidized in the gas stream, but suitably is between room temperature and 350C. For the oxidation of methanol the preferred temperature range is between 50 and 200C. For the oxidation of carbon monoxide the preferred temperature range is between 100 and 200C.
. . .
. .
131~2~
The pressure conditions during the reaction are generally not critical, and the reaction is suitably performed at a pressure between normal atmospheric pressure and 10 bars, preferably at normal (atmospheric~
pres~ure.
The gas velocity is adjusted depending on the reactants. Generally, the gas velocity is in the range of 0.05 to 10 Nl/min x g of the catalyst.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawing~, in which:
Figure 1 is an activity-time diagram;
Figure 2 is a diagram of conversions versus temperature; and Figure 3 is a diagram of activities.
The following examples further explain and illustrate the process according to the invention.
Production of Initial AlloYs (a) Production of amorDhous initial allov A Pd33Zr6~ alloy was produced according to the melt spinning process as the initial alloy for the following tests. Strips with a thickness of 30 microns resulted. The strips were ground for use as catalysts (particle size range, 0~1 to 5 mm)~
(b) Production of crYstalline initial alloY
A crystalline initial alloy was produced by crystallizing out the amorphous initial alloy produced in subsection (a) by treatment thereof in a hi~h vacuum at a temperature of 600C.
(c) Production and activation of a Pd-ZrO2 precipitation catalvst A precipitation catalyst Pd/ZrO2 (1 percent by weight of Pd) was formed according to the following 3 F~ procedure.
The zirconium dioxide present as a granulate ~Harshaw Z~-0304 Tl/8) was finely pulverized. In order to impregnate the powder with 1 percent by weight of Pd, ~r~3 , ! , 131~28 0.2674 ~ of (NH4~2PdC14 per 10 g of ZrO2 was dissolved in a little water. The selected amount of water was ~ust large enough so that the zirconium oxide was completely impregnated. The moist mixture was dried overnight at 120C and the ~d complex was reduced in a hydrogen atmosphere. The reduction conditions were selected as follows:
H2:N2 = 1:10 15 h at 200C, t~en 1 h at 300C, then 1 h at 400C.
Activation of the Initial AlloY
(a) "In situ" activation of an amorphous Pd33Zr67_all_y Pd33Zr67 catalysts (0.30 ~) in the form of chips having a particle size of o.l to 1 mm and a surface area of 0.02 m2/g were activated "in situ" in a reaction flow-through apparatus, in a microreactor made of Pyrex ~lass, with an N2/02/C0 ~as mixture containing 0.17 percent by volume of C0 and 0.17 percent by volume of 2 at temperatures of 202C, 242C and 282C. The ~as flow rate was always 150 Nml/min and the concentration of each of 2 and C0 wa~ 1700 ppm. The tests were conducted at normal atmospheric pressure. The activation times are shown in Figure l.
(b) Activation of an amorphous Pd33Zr67 allov in an air stream The catalysts (0.3 g) were activated in a reaction flow-through apparatus in an air stream at a ~as velocity of 50 Nml/min at normal atmospheric pressure and a temperature of 280C for 1 hour.
(c) "In situ" activation of a crYstalline Pd33Zr67 alloY
Pd33Zr6~ catalysts (0.30 g) in the form of chips havin~ a size of 0.1 to l mm and a surface area of 0.02 m2/~ were activated "in situ'l in a reaction flow-throu~h apparatus, in a microreactor made of Pyrex glass, with an N2~02/C0 gas mixture at 280C. The ~as flow rate was always 150 Nml/min and the concentration of each of 2 and ~31~2~
CO was 1700 ppm. The tests were conducted at normal pressure. The activation time is shown in Figure 1.
(d) Pro~erties of the activated initial alloY in CO
ox_dation Figure 1 summarizes with an activity-time dlagram how the different activation is reflected in the CO oxidation of an amorphous and a crystalline Pd-Zr alloy.
The "in sltu" conditioning resulted in each case ln a higher activity.
When the properties of the amorphous alloy were compared at different temperatures, it was seen that the actlvatlon takes place faster at increasing temperature.
The activation took plane in parallel with the oxidation of the zirconium. X-ray examinations of the majority of the catalysts showed that these consisted of palladium particles, which were embedded in a matrix of Zr oxides.
The activation of the crystalline alloy takes place much slower.
For activation up to stationary activity the following times can be indicated:
In situ activation Oxidation time amorphous 202C about 360 h amorphous 242~C about 65 h amorphous 282C about 10 h crystalline 2B2C about 150 h Table 1 shows the resultant enlarging of the BET
surface during the "in situ" activation of the amorphous sample. Except for the amorphous sample, the surface areas of all 6 catalysts (after the activation) were determined by adsorption of nitrogen.
. ,`, !~ r ., . . ~ , . .
13~928 TABL~ 1 Specific Surface Accordin~ to BET
amorph., amorph., amorph., amorph. support cryst., in situ in situ in situ compari- catalYst in situ son, air Act 202C 242C 282C 280C 280C
Temp.
ABET~
(m2/g) 26.9 29.9 45.9 24.2 45.5 20.2 Note:
ABET of amorphous initial material: 0.031 m2/g (adsorption measured with krypton) Table 2 shows the free metal surface determined by chemisorption measurements.
Metal Surface From Chemisorption Measurements amorph., amorph., amorph., amorph. support cryst., in situ in situ in situ compari- catalvst in situ son, air Act 202C 242C 282C 280C 280C
Temp.
APd ~m2/g) 3.9 5.5 6.9 18.5 0.52 6.9 Disper-sion,% 2.~ 3.9 5.9 13.211.6 5.1 Notes:
APd indicates the metal surface area of the palladium. The dispersion shows in percent the portion of the Pd surface atom relative to the total number of metal atoms.
To the four catalysts shown in Fi~ure 1, two others were added for the tests in Tables 1 and 2, namely:
~ a) A support catalyst with 1 percent by weiqht of Pd on ZrO2 (b) A catalyst activated in an air stream at 280C.
1319~28 EXA_PLE_3Total oxidation of CO with An Amorpkous, Cr~stallin_ and Sup~ort CatalYst After the completed activation phase r the reaction temperature was ~radually reduced and the respective conversion recorded as shown in Fi~ure 2. The ~as velocity was 150 Nml/min in all instances and the concentration of each of 2 and CO was 1~00 ppm. The tests were conducted at normal atmospheric pressure.
From Fi~ure 2, it was established that for the catalysts activated "in situ" there is an increasin~
tendency relative to the activity. Thus, an amorphous catalyst activated "in situ" at 282C was more active than a crystalline catalyst activated at 280C, the latter was again more active than an amorphous catalyst activated "in situ" at 242C and the latter again was more active than an amorphous catalyst activated "in situ" at 202C. It can clearly be seen that the support catalyst exhibited the least activity per gram.
By a determination of the free metal surface area, the activity per catalytically active surface atom was indicated. The reaction rate r was defined as follows:
r = conversion CO ~C02/[atompd.s]
The activity plots contained in the differential conversion are shown in Flgure 3. From Figure 3, it can be seen that an activity property appeared which was dependent on the pretreatment. The discrepancy between support catalyst and the amorphous alloy, which started at 30 280C, is the most obvious. At l/T = 0.003 (=60C), a 14 times ~reater center activity of the catalyst activated "in situ" at 280C appeared, relative to the support catalyst. Thus, it appeared that the type of production of the Pd/ZrO2 affected the nature of the active centers.
Total Oxidation of Methanol A 5 percent by volume methanol-air mixture was passed at 50C over a bed of 0.2 ~ of an amorphous .. , . . , . ; . . ..
1319~28 Pd33~ZrO2)6~ catalyst in the form of chips havin~ a particle size of 0.1 to 1 mm (reaction flow-throu~h apparatus~. The gas flow rate in this case was 300 Nml/m~n. Normal atmospheric pressure was maintained. In the ~as stream at the outlet of the apparatus only C02 and H20 could be detected, i.e., the methanol was quantitatively totally oxidized.
~' ,,
10It is known to use support-bonded noble metal catalysts for the oxidation of carbon monoxide and hydrocarbonQ [Yung-Fana Yu Yao, J. Catal., 8~, 152-162 (1984)]. The process is disadvantageous in that, apart from the use of very expensive noble metal cataly~ts, which render impractical an economical process on a lar~e scale, the reaction temperatures as a rule are set high.
Therefore, from an energy viewpoint, the process i8 even less favorable relative to economic efficiency and costs.
It is also known to use carbon monoxide ln the presence of amorphous metal strlps havln~ the composition Pd35ær65 as a methanizatlon catalyst for C0 and H2 [Yokohama et al., Chemistry Letters, The Chemical Society of Japan, 195-198, (1983)].
An ob~ect of the inventlon is to develop catalysts which do not exhlbit the above discussed drawbac~s.
Accordingly, one a~pect of the invention provldes a flrst class of new activated catalyst of the general formula Pdx(ZrOz)y, wherein x is a number between 301 and 99, y is the difference between x and 100 and æ is a value between 0.5 and 2.
Another aspect of the invention provides a second class of new PdZrO2 precipitation catalysts with a Pd content between 0.2 and 20 percent by weight, produced by the proce6s of:
(a) impre~nating ZrO2 with a water-soluble palladium salt, (b) drying the mixture, and q~
_ . I . A ~ . .
(c~ reducing the Pd complex with hydrogen.
Preferably the activated catalyst of general formula PdxlZrOz)y, wherein x, y and z are as defined above, has the formula Pd33~ZrO2)6~. The activated catalyst is suitably an amorphous or a crystalline alloy.
Production of amorphous alloys is known in the art. An essential feature is that the elements that form the alloys can be premelted under a protective gas, such as, argon. This prealloy is again melted and the melt is 10 finally cooled at a cooling rate of suitably 103 to 109 C~s, preferably 106 to 109 C/s. With this "chilling process", an amorphous phase of the alloy is formed.
Known processes, listed by way of illustration, include the melt spinning process, the splat cool process, and further processes for production of amorphous powders by melting and spraying of the alloy.
According to the invention, crystalline or crystallized alloys of the above defined composition can also be used. Such alloys can be produced in conventional manner,i.e. by melting the initial materials and then permittlng them to cool. It i8 also possible to convert amorphous alloys back to the crystalline state by heating above the crystallization temperature, generally in a high vacuum.
Depending upon the production process, the alloy can be present as strip, pieces of strip, a~ a molded article from strip or in powder form.
In the unactivated state, the catalyst surface area is generally in the range of 0.01 to 0.1 m2/q.
Before their use as catalysts, these alloys according to the invention must first be activated "in situ" or in an oxygen-containing gas stream. Thus, a partial-to-complete oxidation of the zirconium to zirconium oxides of the formula ZrOz, takes place, and z has the above-mentioned meaning. As a rule, most of the palladium remains oxidatively unchanged in the activation, so that the activated catalyst, as X-ray analysis shows, J .`
.'~ .S~
. . , . ~ . .
~319~28 consists mainly of palladium particles which are in a ZrOz matrix.
The phase "in situl' means that the gas mixture containing the reactants, suitably at a temperature 5 between 150 and 350C, and preferably between 200 and 300C, flows over or through the catalyst. After a period of suitably 2 to 400 hours, but generally of 2 to 100 hours, the alloy reaches its full catalytic activity.
Shorter activation times, of 0.1 to 2 hours, are achieved by activation in an air stream. For mere activation, an oxygen-contalnlng gas mixture alone can be used instead of the gas mixture to be reacted.
The reactant activation can be characterized by measurement of the specific surface, e.~., according to the BET method. Thus, a Pdx(ZrOz)y catalyst, depending on the activation, has a specific surface of suitably 15 to 60 m2/g Another method of characterizing the activation is measurement of the metal surface, on the basis of determlnation of chemisorption. The Pdx~ZrOz)~ catalysts according to the invention have, also depending on the activation, a specific metal surface suitably between 2 and 20 m2/g.
The activated catalysts according to the invention are used for the complete oxidation of carbon monoxide, aliphatic and aromatic hydrocarbons as well as aliphatic alcohols in the gas phase. Especially suitable is the process for the total oxidation of ~aid compounds in wa-~te gas streams of fossil combustion units. In this way,the outstanding property of the catalyst according to the invention, namely, the total oxidation of mixtures of said compounds, is emphasized.
The aliphatic hydrocarbons can be saturated or unsaturated, substituted or unsubstituted. Suitable representatives of this class of compounds are, for example, butane, pentane, pentane, hexane and octane.
Representatives aromatic hydrocarbons are, for example, benzene, toluene, ethylbenzene and xylene. As aliphatic , i3~9928 alcohols there may be mentioned shorter-chain compounds such as methanol, ethanol, propanol and butanol, but preferably methanol.
The catalyst according to the invention is especially suitable for the oxidation of carbon monoxide to carbon dioxide and for the total oxidation of methyl alcohol to carbon dioxide and water.
The reaction temperature, i.e. the temperature which is necessary for total oxidation, depends upon the reactant to be oxidized in the gas stream! but suitably is between room temperature and 350C. For the oxidation of methanol the preferred temperature range is between 50 and 200C. For the oxidation of carbon monoxide the preferred temperature range is between 100 and 200~C.
The pressure conditions during the reaction are generally not critical, and the reaction is suitably performed at a pressure between normal atmospheric pressure and 10 bars, preferably at normal atmospheric pressure.
The gas velocity is ad~usted depending on the reactants. Generally, the gas velocity is in the range of 0.05 to lo N1/min x ~ of catalyst.
As mentioned above, the second class of new catalysts of the invention are PdZrO2 precip~tation catalysts with a Pd content between 0.2 and 20 percent by weight produced by a process comprisin~:
(a) impregnating ZrO2 with a water-soluble palladium salt, (b) drying the mixture, and (c) reducing the Pd complex with hydro~en.
According to this aspect of the invention, these catalysts exhibit a Pd content between 0.2 and 20 percent by wei~ht. Preferably, a catalyst with a Pd content of 1 to S percent by weight is used.
3~ The PdZrO2 precipitation catalyst is preferably produced by impre~natin~ a pulverized zirconium oxide having a surface area of 10 to 60 m2/g with a palladium r f~
. .
1319~28 salt dissolved ~n water, dryin~ the moist mixture and reducing the resultant Pd complex with hydroaen.
Palladium chlorides, such as, palladium II
chloride, or complexed palladium chlorides, such as, ammonium tetrach~oropalladate (II), can be used as the water soluble Pd salt.
The reduction is advantageously performed in the presence of a hydro~en-nitrogen mixture in an H2:N2 ratio of between 10 to 1 and 0.1 to 1 at a temperature of 200 to 600~C. The temperature is especially advantageously controlled 50 that the final reduction temperature is reached only after a gradual increase.
Precipitation catalysts of this type are used according to the invention also for the oxidation of carbon monoxide, and the total oxidation of aliphatic and aromatic hydrocarbons, as well as aliphatic alcohols in the gas phase. The process is especially suitable for the total oxidation of such compounds in waste ~as streams.
The aliphatic hydrocarbons can be saturated or unsaturated, substituted or unsubstituted. Suitable representatives of this class of compounds are, for example, butane, pentane, pentane, hexane and octane.
Representative of aromatic hydrocarbons are, for example, benzene, toluene, ethylbenzene and xylene. As aliphatic alcohols there may be mentioned shorter-chain compounds, such as, methanol, ethanol, propanol and butanol, but preferably methanol.
The catalyst accordin~ to this aspect of the invention is especially suitable for the total oxidation of carbon monoxide to carbon dloxide and for the oxidation of methyl alcohol to carbon dioxide and water.
The reaction temperature, i.e. the temperature which is necessary for total oxidation, depends upon reactants to be oxidized in the gas stream, but suitably is between room temperature and 350C. For the oxidation of methanol the preferred temperature range is between 50 and 200C. For the oxidation of carbon monoxide the preferred temperature range is between 100 and 200C.
. . .
. .
131~2~
The pressure conditions during the reaction are generally not critical, and the reaction is suitably performed at a pressure between normal atmospheric pressure and 10 bars, preferably at normal (atmospheric~
pres~ure.
The gas velocity is adjusted depending on the reactants. Generally, the gas velocity is in the range of 0.05 to 10 Nl/min x g of the catalyst.
Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawing~, in which:
Figure 1 is an activity-time diagram;
Figure 2 is a diagram of conversions versus temperature; and Figure 3 is a diagram of activities.
The following examples further explain and illustrate the process according to the invention.
Production of Initial AlloYs (a) Production of amorDhous initial allov A Pd33Zr6~ alloy was produced according to the melt spinning process as the initial alloy for the following tests. Strips with a thickness of 30 microns resulted. The strips were ground for use as catalysts (particle size range, 0~1 to 5 mm)~
(b) Production of crYstalline initial alloY
A crystalline initial alloy was produced by crystallizing out the amorphous initial alloy produced in subsection (a) by treatment thereof in a hi~h vacuum at a temperature of 600C.
(c) Production and activation of a Pd-ZrO2 precipitation catalvst A precipitation catalyst Pd/ZrO2 (1 percent by weight of Pd) was formed according to the following 3 F~ procedure.
The zirconium dioxide present as a granulate ~Harshaw Z~-0304 Tl/8) was finely pulverized. In order to impregnate the powder with 1 percent by weight of Pd, ~r~3 , ! , 131~28 0.2674 ~ of (NH4~2PdC14 per 10 g of ZrO2 was dissolved in a little water. The selected amount of water was ~ust large enough so that the zirconium oxide was completely impregnated. The moist mixture was dried overnight at 120C and the ~d complex was reduced in a hydrogen atmosphere. The reduction conditions were selected as follows:
H2:N2 = 1:10 15 h at 200C, t~en 1 h at 300C, then 1 h at 400C.
Activation of the Initial AlloY
(a) "In situ" activation of an amorphous Pd33Zr67_all_y Pd33Zr67 catalysts (0.30 ~) in the form of chips having a particle size of o.l to 1 mm and a surface area of 0.02 m2/g were activated "in situ" in a reaction flow-through apparatus, in a microreactor made of Pyrex ~lass, with an N2/02/C0 ~as mixture containing 0.17 percent by volume of C0 and 0.17 percent by volume of 2 at temperatures of 202C, 242C and 282C. The ~as flow rate was always 150 Nml/min and the concentration of each of 2 and C0 wa~ 1700 ppm. The tests were conducted at normal atmospheric pressure. The activation times are shown in Figure l.
(b) Activation of an amorphous Pd33Zr67 allov in an air stream The catalysts (0.3 g) were activated in a reaction flow-through apparatus in an air stream at a ~as velocity of 50 Nml/min at normal atmospheric pressure and a temperature of 280C for 1 hour.
(c) "In situ" activation of a crYstalline Pd33Zr67 alloY
Pd33Zr6~ catalysts (0.30 g) in the form of chips havin~ a size of 0.1 to l mm and a surface area of 0.02 m2/~ were activated "in situ'l in a reaction flow-throu~h apparatus, in a microreactor made of Pyrex glass, with an N2~02/C0 gas mixture at 280C. The ~as flow rate was always 150 Nml/min and the concentration of each of 2 and ~31~2~
CO was 1700 ppm. The tests were conducted at normal pressure. The activation time is shown in Figure 1.
(d) Pro~erties of the activated initial alloY in CO
ox_dation Figure 1 summarizes with an activity-time dlagram how the different activation is reflected in the CO oxidation of an amorphous and a crystalline Pd-Zr alloy.
The "in sltu" conditioning resulted in each case ln a higher activity.
When the properties of the amorphous alloy were compared at different temperatures, it was seen that the actlvatlon takes place faster at increasing temperature.
The activation took plane in parallel with the oxidation of the zirconium. X-ray examinations of the majority of the catalysts showed that these consisted of palladium particles, which were embedded in a matrix of Zr oxides.
The activation of the crystalline alloy takes place much slower.
For activation up to stationary activity the following times can be indicated:
In situ activation Oxidation time amorphous 202C about 360 h amorphous 242~C about 65 h amorphous 282C about 10 h crystalline 2B2C about 150 h Table 1 shows the resultant enlarging of the BET
surface during the "in situ" activation of the amorphous sample. Except for the amorphous sample, the surface areas of all 6 catalysts (after the activation) were determined by adsorption of nitrogen.
. ,`, !~ r ., . . ~ , . .
13~928 TABL~ 1 Specific Surface Accordin~ to BET
amorph., amorph., amorph., amorph. support cryst., in situ in situ in situ compari- catalYst in situ son, air Act 202C 242C 282C 280C 280C
Temp.
ABET~
(m2/g) 26.9 29.9 45.9 24.2 45.5 20.2 Note:
ABET of amorphous initial material: 0.031 m2/g (adsorption measured with krypton) Table 2 shows the free metal surface determined by chemisorption measurements.
Metal Surface From Chemisorption Measurements amorph., amorph., amorph., amorph. support cryst., in situ in situ in situ compari- catalvst in situ son, air Act 202C 242C 282C 280C 280C
Temp.
APd ~m2/g) 3.9 5.5 6.9 18.5 0.52 6.9 Disper-sion,% 2.~ 3.9 5.9 13.211.6 5.1 Notes:
APd indicates the metal surface area of the palladium. The dispersion shows in percent the portion of the Pd surface atom relative to the total number of metal atoms.
To the four catalysts shown in Fi~ure 1, two others were added for the tests in Tables 1 and 2, namely:
~ a) A support catalyst with 1 percent by weiqht of Pd on ZrO2 (b) A catalyst activated in an air stream at 280C.
1319~28 EXA_PLE_3Total oxidation of CO with An Amorpkous, Cr~stallin_ and Sup~ort CatalYst After the completed activation phase r the reaction temperature was ~radually reduced and the respective conversion recorded as shown in Fi~ure 2. The ~as velocity was 150 Nml/min in all instances and the concentration of each of 2 and CO was 1~00 ppm. The tests were conducted at normal atmospheric pressure.
From Fi~ure 2, it was established that for the catalysts activated "in situ" there is an increasin~
tendency relative to the activity. Thus, an amorphous catalyst activated "in situ" at 282C was more active than a crystalline catalyst activated at 280C, the latter was again more active than an amorphous catalyst activated "in situ" at 242C and the latter again was more active than an amorphous catalyst activated "in situ" at 202C. It can clearly be seen that the support catalyst exhibited the least activity per gram.
By a determination of the free metal surface area, the activity per catalytically active surface atom was indicated. The reaction rate r was defined as follows:
r = conversion CO ~C02/[atompd.s]
The activity plots contained in the differential conversion are shown in Flgure 3. From Figure 3, it can be seen that an activity property appeared which was dependent on the pretreatment. The discrepancy between support catalyst and the amorphous alloy, which started at 30 280C, is the most obvious. At l/T = 0.003 (=60C), a 14 times ~reater center activity of the catalyst activated "in situ" at 280C appeared, relative to the support catalyst. Thus, it appeared that the type of production of the Pd/ZrO2 affected the nature of the active centers.
Total Oxidation of Methanol A 5 percent by volume methanol-air mixture was passed at 50C over a bed of 0.2 ~ of an amorphous .. , . . , . ; . . ..
1319~28 Pd33~ZrO2)6~ catalyst in the form of chips havin~ a particle size of 0.1 to 1 mm (reaction flow-throu~h apparatus~. The gas flow rate in this case was 300 Nml/m~n. Normal atmospheric pressure was maintained. In the ~as stream at the outlet of the apparatus only C02 and H20 could be detected, i.e., the methanol was quantitatively totally oxidized.
~' ,,
Claims (18)
1. An activated catalyst of the general formula Pdx(ZrOz)y, wherein x is a number between 1 and 99, y is the difference between x and 100 and z is a value between 0.5 and 2.
2. An activated catalyst according to claim 1, wherein x is 33, y is 67 and z is 2.
3. An activated catalyst according to claim 1 or 2, wherein the catalyst is an amorphous alloy.
4. An activated catalyst according to claim 1 or 2, wherein the catalyst is a crystalline or crystallized alloy.
5. An activated catalyst according to claim 1 or 2, wherein starting from a PdxZry alloy, wherein x and y have the indicated meanings, activation takes place in situ in a gas stream containing reactants or in an oxygen-containing gas stream at a temperature between 150° and 350°C.
6. A process for the total oxidation of carbon monoxide, an aliphatic or aromatic hydrocarbon or an aliphatic alcohol, which comprises reacting the compound in an oxygen-containing gas stream in the presence of an activated catalyst of the general formula Pdx(ZrO2)y, wherein x is a number between 1 and 99, y is the difference between x and 100 and z is a value between 0.5 and 2, in the form of a crystalline or amorphous alloy, at a temperature between room temperature and 350°C and at a pressure from normal atmospheric pressure to 10 bars.
7. A process according to claim 6 for the total oxidation of carbon monoxide, wherein an air stream containing from 100 ppm to 50 percent by volume of carbon monoxide is conducted over the activated Pdx(ZrOz)y catalyst.
8. A process according to claim 7, wherein the temperature is between 100° and 200°C, and the pressure is normal atmospheric pressure.
9. A process according to claim 6 for the total oxidation of methyl alcohol, wherein an air stream containing from 100 ppm to 7 percent by volume or more than 36 percent by volume of methyl alcohol is conducted over the activated Pdx(ZrOz)y catalyst.
10. A process according to claim 9, wherein the temperature is between 50° and 200°C, and the pressure is normal atmospheric pressure.
11. A PdZrO2 precipitation catalyst with a Pd content between 0.2 and 20 percent by weight, produced by a process comprising:
(a) impregnating ZrO2 with a water-soluble palladium salt, (b) drying the mixture, and (c) reducing the Pd complex with hydrogen.
(a) impregnating ZrO2 with a water-soluble palladium salt, (b) drying the mixture, and (c) reducing the Pd complex with hydrogen.
12. A precipitation catalyst according to claim 11, wherein the Pd content is from 1 to 5 percent by weight.
13. A precipitation catalyst according to claim 11, wherein a palladium chloride or a complexed palladium chloride is used as the water-soluble Pd salt.
14. A precipitation catalyst according to claim 11, 12 or 13, wherein the drying of the mixture is carried out at a temperature of 120° to 300°C.
15. A precipitation catalyst according to claim 11, 12 or 13, wherein the reduction takes place with a hydrogen-nitrogen mixture in an H2:N2 ratio of between 10 to 1 and 0.1 to 1 at a temperature between 200° and 600°C.
16. A process for the total oxidation of carbon monoxide, an aliphatic or aromatic hydrocarbon or an aliphatic alcohol which comprises reacting the compound in an oxygen-containing gas stream in the presence of a PdZrO2 precipitation catalyst as defined in claim 11, at a temperature between room temperature and 350°C and a pressure from normal atmospheric pressure to 10 bars.
17. A process according to claim 16, for the total oxidation of carbon monoxide, wherein an air stream containing 100 ppm to 50 percent by volume of carbon monoxide is conducted over the activated PdZrOZ2 precipitation catalyst.
18. A process according to claim 17, wherein the temperature is between 100° and 200°C, and the pressure is normal atmospheric pressure.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CH268587 | 1987-07-14 | ||
| CH2685/87 | 1987-07-14 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1319928C true CA1319928C (en) | 1993-07-06 |
Family
ID=4239274
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000571915A Expired - Fee Related CA1319928C (en) | 1987-07-14 | 1988-07-13 | Catalyst for the oxidation of carbon compounds |
Country Status (7)
| Country | Link |
|---|---|
| US (2) | US4916109A (en) |
| EP (1) | EP0299485B1 (en) |
| JP (1) | JPS6434443A (en) |
| AT (1) | ATE81307T1 (en) |
| CA (1) | CA1319928C (en) |
| DE (1) | DE3875173D1 (en) |
| ES (1) | ES2043740T3 (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0402122B2 (en) * | 1989-06-07 | 1998-03-18 | Ngk Insulators, Ltd. | Method for treating exhaust gas |
| US5254797A (en) * | 1989-06-07 | 1993-10-19 | Ngk Insulators, Ltd. | Method of treating exhaust gas |
| GB9226453D0 (en) * | 1992-12-18 | 1993-02-10 | Johnson Matthey Plc | Metal oxide catalyst |
| US6524550B1 (en) * | 1999-05-03 | 2003-02-25 | Prashant S. Chintawar | Process for converting carbon monoxide and water in a reformate stream |
| US20070169852A1 (en) * | 2003-04-07 | 2007-07-26 | Akihisa Inoue | Hydrogen storage alloy material and process for producing the same |
| JP4622753B2 (en) * | 2005-09-05 | 2011-02-02 | マツダ株式会社 | Diesel particulate filter with catalyst |
| KR101555924B1 (en) * | 2013-11-18 | 2015-09-30 | 코닝정밀소재 주식회사 | Oxidation catalyst, method of fabricating thereof and filter for purifying exhaust gas including the same |
Family Cites Families (50)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US670775A (en) * | 1899-12-15 | 1901-03-26 | Harleston Corbett Gesner | Process of making alloys of iron and hydrogen. |
| US1735763A (en) * | 1927-08-08 | 1929-11-12 | Selden Co | Catalytic oxidation of organic compounds |
| GB436906A (en) * | 1933-06-22 | 1935-10-21 | Degea Ag Auergesellschaft | Improvements in and relating to catalysts serving for the removal of bad odours and poison from the exhaust gases of internal combustion engines |
| US2744062A (en) * | 1952-05-15 | 1956-05-01 | Birmingham Small Arms Co Ltd | Production of metallic powders |
| GB996987A (en) * | 1962-07-03 | 1965-06-30 | British Aluminium Co Ltd | Improvements in or relating to methods of breaking up sintered compacted metal bodies |
| US3271327A (en) * | 1963-05-29 | 1966-09-06 | Air Prod & Chem | Preparation of supported palladium catalysts |
| US3376107A (en) * | 1963-10-10 | 1968-04-02 | Oka Akira | Stoichiometric transition metal hydrides |
| US3363846A (en) * | 1965-12-16 | 1968-01-16 | Nuclear Materials & Equipment | Method of and apparatus for producing small particles |
| US3914377A (en) * | 1972-07-07 | 1975-10-21 | Mobil Oil Corp | Catalyst reactor for oxidizing carbon monoxide and hydrocarbons in gaseous stream |
| US3830756A (en) * | 1972-08-04 | 1974-08-20 | Grace W R & Co | Noble metal catalysts |
| US3871836A (en) * | 1972-12-20 | 1975-03-18 | Allied Chem | Cutting blades made of or coated with an amorphous metal |
| US3856513A (en) * | 1972-12-26 | 1974-12-24 | Allied Chem | Novel amorphous metals and amorphous metal articles |
| US3856074A (en) * | 1973-04-06 | 1974-12-24 | Allied Chem | Method of centrifugal production of continuous metal filaments |
| US3862658A (en) * | 1973-05-16 | 1975-01-28 | Allied Chem | Extended retention of melt spun ribbon on quenching wheel |
| GB1505841A (en) * | 1974-01-12 | 1978-03-30 | Watanabe H | Iron-chromium amorphous alloys |
| US3992476A (en) * | 1974-06-19 | 1976-11-16 | Universal Oil Products Company | Paraffin isomerizaton with a catalytic composite of platinum or palladium metal, rhodium metal, tin oxide, halogen and alumina carrier |
| US3989517A (en) * | 1974-10-30 | 1976-11-02 | Allied Chemical Corporation | Titanium-beryllium base amorphous alloys |
| US3981722A (en) * | 1974-10-31 | 1976-09-21 | Allied Chemical Corporation | Amorphous alloys in the U-Cr-V system |
| DE2509251C3 (en) * | 1975-03-04 | 1978-07-13 | Hoechst Ag, 6000 Frankfurt | Process for the preparation of a palladium catalyst |
| US4018839A (en) * | 1975-06-06 | 1977-04-19 | Uop Inc. | Hydrocarbon isomerization process |
| SE433178B (en) * | 1975-10-31 | 1984-05-14 | Johnson Matthey Co Ltd | Catalytic converter for the cleaning of car exhaust of the general type A? 71XM? 71YO? 71Z |
| DE2555131C2 (en) * | 1975-12-08 | 1986-05-07 | Eumann, Hanns-Heinz, 7034 Gärtringen | Ion exchange filter |
| US4142571A (en) * | 1976-10-22 | 1979-03-06 | Allied Chemical Corporation | Continuous casting method for metallic strips |
| US4233185A (en) * | 1976-12-08 | 1980-11-11 | Johnson, Matthey & Co., Limited | Catalysts for oxidation and reduction |
| GB1595628A (en) * | 1977-03-07 | 1981-08-12 | Furukawa Electric Co Ltd | Method of producing amorphous metal tapes |
| US4179581A (en) * | 1977-04-18 | 1979-12-18 | Uop Inc. | Paraffinic hydrocarbon isomerization process |
| CA1123818A (en) * | 1977-08-05 | 1982-05-18 | Anthony Gartshore | Catalyst for purification and/or control of exhaust gases |
| GB1604924A (en) * | 1978-05-26 | 1981-12-16 | Ozyagcitar M N | Synthesis of hydrocarbons and alcohols using an alloy catalyst |
| JPS5547636A (en) * | 1978-10-02 | 1980-04-04 | Asahi Chem Ind Co Ltd | Preparation of o-phenylphenol and its precursor |
| US4221257A (en) * | 1978-10-10 | 1980-09-09 | Allied Chemical Corporation | Continuous casting method for metallic amorphous strips |
| US4331739A (en) * | 1978-10-10 | 1982-05-25 | Allied Corporation | Amorphous metallic strips |
| US4197146A (en) * | 1978-10-24 | 1980-04-08 | General Electric Company | Molded amorphous metal electrical magnetic components |
| US4201837A (en) * | 1978-11-16 | 1980-05-06 | General Electric Company | Bonded amorphous metal electromagnetic components |
| US4300946A (en) * | 1979-05-17 | 1981-11-17 | Billings Energy Corporation | Granulating and activating metal to form metal hydride |
| JPS55155739A (en) * | 1979-05-23 | 1980-12-04 | Toyota Central Res & Dev Lab Inc | Exhaust gas purifying catalyzer |
| US4304593A (en) * | 1979-11-14 | 1981-12-08 | Allied Chemical Corporation | Embrittling of glass alloys by hydrogen charging |
| EP0034403A1 (en) * | 1980-01-17 | 1981-08-26 | The University of South Carolina | Method of making ammonia |
| FR2482953A1 (en) * | 1980-05-22 | 1981-11-27 | Inst Francais Du Petrole | METHOD FOR SELECTIVE HYDROGENATION OF DI-OLEFIN IN A MIXTURE OF HYDROCARBONS COMPRISING AT LEAST 4 ATOMS OF CARBON AND CONTAINING OLEFIN -A |
| ZA814007B (en) * | 1980-06-18 | 1982-10-27 | Oezyagcilar Mehmet N | Method for the coproduction of hydrocarbons and alcohols |
| JPS6046186B2 (en) * | 1981-06-03 | 1985-10-15 | 東ソー株式会社 | Activation method for amorphous metal surfaces |
| JPS57209236A (en) * | 1981-06-19 | 1982-12-22 | Sumitomo Chem Co Ltd | Preparation of methanol |
| JPS58159847A (en) * | 1982-03-19 | 1983-09-22 | Hiroyoshi Inoue | Amorphous alloy type catalyst for reduction reaction |
| JPS6059034A (en) * | 1983-09-13 | 1985-04-05 | Takeshi Masumoto | Fine wire of amorphous cu-zr alloy |
| ATE39849T1 (en) * | 1983-09-27 | 1989-01-15 | Uop Inc | CATALYST AND METHOD OF TREATMENT OF EXHAUST GASES. |
| US4572904A (en) * | 1983-09-27 | 1986-02-25 | Signal Applied Technologies Inc. | Lead-tolerant catalyst system for treating exhaust gas containing lead compounds |
| JPS60190236A (en) * | 1984-03-12 | 1985-09-27 | Nippon Shokubai Kagaku Kogyo Co Ltd | Preparation of catalyst having high temperature heat resistance |
| CH660130A5 (en) * | 1984-07-27 | 1987-03-31 | Lonza Ag | METHOD FOR THE PRODUCTION OF CATALYTICALLY EFFECTIVE, GLASS-FREEZING METALS. |
| JPS6297646A (en) * | 1985-10-25 | 1987-05-07 | Matsushita Electric Ind Co Ltd | Catalyst for purifying exhaust gas and its preparation |
| JPS63116744A (en) * | 1986-11-05 | 1988-05-21 | Matsushita Electric Ind Co Ltd | Catalyst for purifying exhaust gas and its preparation |
| US4859434A (en) * | 1988-06-10 | 1989-08-22 | Air Products And Chemicals, Inc. | Production of endothermic gases with methanol |
-
1988
- 1988-07-12 JP JP63173638A patent/JPS6434443A/en active Pending
- 1988-07-13 US US07/220,796 patent/US4916109A/en not_active Expired - Fee Related
- 1988-07-13 CA CA000571915A patent/CA1319928C/en not_active Expired - Fee Related
- 1988-07-14 AT AT88111336T patent/ATE81307T1/en not_active IP Right Cessation
- 1988-07-14 ES ES88111336T patent/ES2043740T3/en not_active Expired - Lifetime
- 1988-07-14 DE DE8888111336T patent/DE3875173D1/en not_active Expired - Fee Related
- 1988-07-14 EP EP88111336A patent/EP0299485B1/en not_active Expired - Lifetime
-
1989
- 1989-01-04 US US07/293,442 patent/US4978513A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| US4916109A (en) | 1990-04-10 |
| ES2043740T3 (en) | 1994-01-01 |
| EP0299485A1 (en) | 1989-01-18 |
| DE3875173D1 (en) | 1992-11-12 |
| JPS6434443A (en) | 1989-02-03 |
| ATE81307T1 (en) | 1992-10-15 |
| EP0299485B1 (en) | 1992-10-07 |
| US4978513A (en) | 1990-12-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100447463B1 (en) | Catalyst and process for the preparation of hydrocarbons | |
| Ertl et al. | Preparation of solid catalysts | |
| EP0191373B1 (en) | Co hydrogenation with molybdenum on wide-pore carbon catalysts | |
| Klier et al. | Catalytic synthesis of methanol from COH2: IV. The effects of carbon dioxide | |
| EP0434284B1 (en) | Selective catalysts and their preparation for catalytic hydrocarbon synthesis | |
| CA1261883A (en) | Process for producing lower aliphatic alcohols | |
| KR100818900B1 (en) | A method for catalytic conversion of carbon monoxide in a hydrogen-containing gas mixture | |
| CA1182809A (en) | Hydrocarbon synthesis catalyst and method of preparation and use thereof | |
| Baiker et al. | Carbon-Monoxide Oxidation over Catalysts Prepared by in-Situ Activation of Amorphous Gold-Silver-Zirconium and Gold-Iron-Zirconium Alloys | |
| US4154751A (en) | Preparation and use of supported potassium (or rubidium)-Group VIII-metal cluster catalysts in CO/H2 Fischer-Tropsch synthesis reactions | |
| JPS6339634A (en) | Conversion of synthetic gas using ror-activated catalyst | |
| Cabet et al. | Synthesis of new Fe–Co based metal/oxide composite materials: application to the Fischer–Tropsch synthesis | |
| Fujitani et al. | Methanol synthesis from CO and CO2 hydrogenations over supported palladium catalysts | |
| US5118715A (en) | Selective fixed-bed fischer-tropsch synthesis with high surface area Cu and K promoted, iron/manganese spinels | |
| CA1319928C (en) | Catalyst for the oxidation of carbon compounds | |
| EP0101645B1 (en) | Catalytic process for the production of methanol | |
| US10124320B1 (en) | Vanadium oxide catalyst supported on CeO2—ZrO2 for dimethyl ether production via oxidative dehydration of methanol | |
| Das et al. | Conversion of syngas to light olefins over silicalite-1 supported iron and cobalt catalysts: Effect of manganese addition | |
| Cao et al. | The oxidative dehydrogenation of methanol over a novel Ag/SiO2 catalyst | |
| US4579995A (en) | Process for the conversion of methanol to hydrocarbons | |
| JPS58159847A (en) | Amorphous alloy type catalyst for reduction reaction | |
| US4206135A (en) | Catalyst comprising nickel supported on tantalum oxide or niobium oxide and their use as hydrocarbon synthesis catalysts in CO/H2 reactions | |
| Fierro | Hydrogenation of carbon oxides over perovskite-type oxides | |
| US4925824A (en) | Iron catalyst for preparation of polymethylene from synthesis gas and method for producing the catalyst | |
| Bañares et al. | Novel cluster-derived catalysts for the selective hydrogenation of crotonaldehyde |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |