Exxon Research and Engineering Company

M Albert Vannice

Robert L Garten

Gary Brice McVicker

Samuel J Tauster

This invention relates to unique supported potassium (or rubidium) - Group VIII-metal cluster catalysts which are useful in CO/H.sub.2 reactions (Fischer-Tropsch synthesis reactions). The novel catalysts of the instant invention are prepared by depositing well characterized potassium (or rubidium) - Group VIII-metal carbonyl cluster complexes onto high surface area supports. Following a subsequent reduction, the precursor bimetallic cluster complexes are decomposed on the support surface forming a potassium (or rubidium) promoted Group VIII-metal cluster catalyst in which the potassium (or rubidium) and Group VIII metals are intimately associated. These unique, highly promoted cluster catalysts have been found to demonstrate high Group VIII-metal dispersions and enhanced Fischer-Tropsch activities and selectivities for producing olefinic and paraffinic hydrocarbons. In addition methane formation is dramatically reduced over the supported bimetallic cluster catalysts of the instant invention when compared to conventionally prepared supported potassium (or rubidium) promoted Group VIII-metal catalysts.

Preparation and use of supported potassium (or rubidium)-Group

An improved method for the synthesis of hydrocarbons with reduced methane formation and for the selective generation of olefinic hydrocarbons, preferably C.sub.2 -C.sub.5 olefins inclusive, which method comprises the steps of passing a CO and H.sub.2 synthesis gas stream over a catalyst at a temperature and pressure for a time sufficient to generate the desired olefinic products, wherein the improvement consists in using as a catalyst ruthenium on a support comprising at least one refractory Group VB metal oxide. The weight loading of the ruthenium may range from about 0.01 to about 15 wt. % based on the total catalyst weight. The ruthenium average crystallite size is preferably less than 5 nm (50A). The operating conditions of the instant process are typical for Fischer-Tropsch synthesis.

Hydrocarbon synthesis from CO and H.sub.2 using Ru supported on group VB

This invention relates to unique supported potassium (or rubidium)-Group VIII-metal cluster catalysts which are useful in CO/H.sub.2 reactions (Fischer-Tropsch synthesis reactions). The novel catalysts of the instant invention are prepared by depositing well characterized potassium (or rubidium)-Group VIII-metal carbonyl cluster complexes onto high surface area supports. Following a subsequent reduction, the precursor bimetallic cluster complexes are decomposed on the support surface forming a potassium (or rubidium) promoted Group VIII-metal cluster catalyst in which the potassium (or rubidium) and Group VIII metals are intimately associated. These unique, highly promoted cluster catalysts have been found to demonstrate high Group VIII-metal dispersions and enhanced Fischer-Tropsch activities and selectivities for producing olefinic and paraffinic hydrocarbons. In addition methane formation is dramatically reduced over the supported bimetallic cluster catalysts of the instant invention when compared to conventionally prepared supported potassium (or rubidium) promoted Group VIII-metal catalysts.

A new method for the selective synthesis of olefinic hydrocarbons of from C.sub.2 -C.sub.5 from CO and H.sub.2 which method comprises the steps of passing a synthesis gas stream of CO and H.sub.2 at a H.sub.2 /CO ratio of from 0.1-10 at a space velocity of from 100 hr..sup.-1 to 50,000 hr..sup.-1 over a catalyst system comprising from 0.01 to 10 wt. % rhodium deposited on TiO.sub.2, other titanium-containing oxides or mixtures of said titanium-containing oxides for a time sufficient to effect the generation of desired olefinic products, at a temperature of from 100.degree.-500.degree. C. and a pressure of from 100 to 10.sup.5 kPa. The supported rhodium catalyst has a surface area of from 10 to 60 m.sup.2 g.sup.-1 of total catalyst with a preferred rhodium crystallite size .ltoreq. 5 nm. Rhodium supported on TiO.sub.2, other titanium-containing oxides, or mixtures of titanium oxides results in a catalyst system which exhibits superior hydrocarbon synthesis characteristics. Such supported rhodium catalysts exhibit selectivity to olefinic products of from 2 to 5 carbons inclusive in processes for olefin generation accompanied by greater product yields and exhibit improved longevity, tolerance to sulfur and activity maintenance.

Hydrocarbon synthesis from CO and H.sub.2 using Rh supported on titanium

A method for producing low molecular weight organic compounds, said method comprising the step of passing a mixture of CO and H.sub.2 over palladium supported on a suitable acidic metal oxide at a temperature and pressure sufficient to form said organic compounds. The palladium is highly dispersed on the chosen support and has a crystallite size of less than 100 A, preferably less than 70 A, most preferably, less than 40 A. In this state, the surface Pd atoms have a much higher activity than surface Pd atoms of very large Pd crystallites. To insure maintenance of such high activity and small crystallite size for a substantial period during the course of the reaction, the synthesis reactions are run at reactor bed temperatures below which agglomeration of crystallites is avoided, i.e., at temperatures below 350.degree. C., preferably about 325.degree. C., most preferably 300.degree. C.

Catalytic formation of hydrocarbons from CO, H.sub.2 mixtures and

Nickel supported on TiO.sub.2, other titanium-containing oxides or mixtures of various titanium oxides results in a catalyst system which exhibits superior hydrocarbon synthesis characteristics. Such supported nickel catalysts exhibit selectivity to paraffinic hydrocarbon products of from C.sub.2 to C.sub.7 which are free of olefins and oxygenated products. They generate CO conversions of up to 60% at pressures of 3090 kPa without significant change in product distribution. A large fraction of the product obtained contains 2 or more carbon atoms in the chain up to conversions of 60%. The supported nickel catalysts exhibit enhanced activity, improved selectivity to higher molecular weight normal paraffins, improved longevity and tolerance to sulfur and resistance to nickel carbonyl formation as compared to nickel catalysts on other supports such as Al.sub.2 O.sub.3, silica or carbon. A new method for the selective synthesis of higher molecular weight normal paraffins from CO and H.sub.2 over a wide range of CO conversions at pressures of from 103 to 3090 kPa (1 atm=103 kPa) which method comprises the steps of passing a synthesis gas stream of CO and H.sub.2 at a ratio of from 2 moles CO per .2 to 20 moles H.sub.2 at a space velocity of from 100 hr..sup.-.sup.1 to 30,000 hr..sup.-.sup.1 over a catalyst comprising from 0.01 to 75 wt. % nickel on TiO.sub.2, other titanium-containing oxides or mixtures of said titanium-containing oxides for a time sufficient to effect the generation of desired paraffinic products, at a temperature of from 100 to 500.degree. C. and a pressure of from 103 to 1.03 .times. 10.sup.5 kPa. The supported nickel catalyst has a BET surface area of from 10 to 60 m.sup.2 g.sup..sup.-1 of total catalyst with a nickel crystallite size of &lt; 10 nm (100 A).

Hydrocarbon synthesis from CO and H.sub.2 using Ni supported on a

A new method for the synthesis of hydrocarbons with chain lengths of from 2 to 10 carbon atoms inclusive and for selective generation of olefinic hydrocarbons in this carbon number range with reduced wax formation, said products being synthesized from CO and H.sub.2 at pressures of from 100 to 3100 kPa which method comprises the steps of passing a synthesis gas stream of CO and H.sub.2 at a H.sub.2 /CO ratio of from 0.1-10 at a space velocity of from 100 hr.sup.-.sup.1 to 50,000 hr.sup.-.sup.1 over a catalyst comprising from 0.01 to 15 wt. % ruthenium on TiO.sub.2, other titanium-containing oxides or mixtures of said titanium-containing oxides for a time sufficient to effect the generation of desired olefinic hydrocarbon products, at a temperature of from 100.degree. to 500.degree. C and a pressure of from 100 to 10.sup.5 kPa (1-1000 atm). The supported ruthenium catalyst has a BET surface area of from 10 to 60 m.sup.2 g.sup.-1 of total catalyst with a ruthenium crystallite size of preferably less than 5 nm (50 A).

Hydrocarbon synthesis from CO and H.sub.2 using Ru supported on a

Halogenated hydrocarbons are selectively prepared under mild reaction conditions by flowing a gaseous mixture of H.sub.2, CO, and halogen selected from the group consisting of chlorine, bromine and iodine over a well-dispersed supported catalyst system, such as Pt/Re, Pt/Ir, Pt, Ir and Re on an acidic support such as Al.sub.2 O.sub.3, SiO.sub.2 -Al.sub.2 O.sub.3 or zeolites. The reaction occurs over a broad temperature range of from 200.degree. to 1,000.degree. C and a pressure of from 0.1 to 500 atmospheres.

Method for the direct preparation of halogenated hydrocarbons by the

A method for producing ethane, ethylene and dimethyl ether compounds, said method comprising the step of passing a mixture of CO and hydrogen over platinum supported on alumina at a temperature ranging from 100.degree.C. to 400.degree.C. and a pressure ranging from 1 to 100 atmospheres.

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Boalsburg, PA, United States of America

M Albert Vannice