Abstract: Crystalline molecular sieves having three-dimensional microporous framework structure of MO.sub.2, AlO.sub.2, and PO.sub.2 tetrahedral oxide units are disclosed. These molecular sieves have an empirical chemical composition on an anhydrous basis are expressed by the formula:mR: (M.sub.x Al.sub.y P.sub.z)O.sub.2wherein "R" represents at least one organic templating agent present in the intracrystalline pore system; "m" represents the molar amount of "R" present per mole of (M.sub.x Al.sub.y P.sub.z)O.sub.2 ; "M" represents at least two elements capable of forming framework tetrahedral oxides and selected from the group consisting of arsenic, beryllium, boron, chromium, gallium, germanium, lithium and vanadium; and "x", "y" and "z" represent the mole fractions of "M", aluminum and phosphorus, respectively, present as tetrahedral oxides. Their use as adsorbents, catalysts, etc. is disclosed. The catalyst is useful in the cracking and hydrocracking of various hydrocarbonaceous feeds.

Abstract: A reactor system for conducting chemical reactions including dehydrogenation reactions and a method for conducting chemical reactions including dehydrogenation reactions therein is disclosed. The reactor comprises a mixing means and a reactor zone comprising a reactor conduit having a shell or housing and at least one inner conduit extending through a major portion of the reactor shell. The mixing means is in fluid communication with the reaction zone. The inner conduit comprise openings or injectors for introducing, at a plurality of locations through the reactor conduit, either additional amounts of the control and/or reactant fluids into the stream of the reactant or, alternatively, the reaction mixture into a stream of the control and/or reactant fluid.

Abstract: Diisopropenylbenzene is a monomer that can be used in the preparation of many useful polymers and is also a chemical intermediate that can be employed in a number of chemical processes. Diisopropenylbenzene is normally synthesized by the dehydrogenation of diisopropylbenzene. Unfortunately in this dehydrogenation process a number of olefinic impurities are produced as by-products. This invention discloses a process for the separation of diisopropenylbenzene from these impurities and for recycling some of the impurities.

Abstract: Saturated hydrocarbon is transformed catalytically into olefinic hydrocarbon of corresponding skeletal configuration by reacting the saturated hydrocarbon with a suitable alkene cyclopentadienyl or alkene arene transition metal molecular complex, such as bis(ethylene)pentamethylcyclopentadienyliridium, bis(ethylene)pentamethylcyclopentadienylrhodium and bis(ethylene)hexamethylbenzene osmium in the presence of free alkene as hydrogen acceptor. The reaction may be performed photochemically under irradiation with ultraviolet light or it may be performed thermolytically under application of heat. The catalyst may be charged to the reaction as a preformed alkene cyclopentadienyl or alkene arene transition metal molecular complex or the catalyst may be formed in situ in the reaction mixture via displacement of ligand from a suitable transition metal complex containing the displaceable ligand, such as dicarbonylpentamethylcyclopentadienyliridium or cyclooctadienepentamethylcyclopentadienyliridium.

Abstract: Dehydrogenatable hydrocarbons may be subjected to a dehydrogenation reaction in which the hydrocarbons are treated with a dehydrogenation catalyst comprising a modified iron catalyst in the presence of steam in a multicatalyst bed system. The reaction mixture containing unconverted hydrocarbons, dehydrogenated hydrocarbons, hydrogen and steam is then contacted with an oxidation catalyst whereby hydrogen is selectively oxidized. The selective oxidation catalyst which is used will comprise a noble metal of Group VIII of the Periodic Table, a metal of Group IVA and, if so desired, a metal of Group IA or IIA composited on a porous inorganic support. The inorganic support will comprise an alumina precursor which possesses and ABD less than about 0.6 g/cc, a pore volume greater than about 0.5 cc/g, and a pore distribution such that between 10% and 70% of the pore volume is present as pores whose diameters are greater than about 300 Angstroms. After peptizing and calcination at a temperature of about 900.degree.

Abstract: The invention is an improved method and apparatus for recovering waste heat from a low temperature process stream by means of a vaporizable heat sink liquid, characterized by an effective lowering of the boiling temperature of the heat sink liquid without need to reduce its boiling pressure. The heat sink liquid essentially comprises a mixture of two immiscible liquids that form a low boiling azeotrope. The heat sink liquid is brought into indirect heat exchange with the low temperature process stream for heat extraction. The invention involves simultaneous boiling of the two immiscible liquids to suppress the temperature of the heat sink liquid to below the low temperature of the process stream, whereby the heat sink liquid is able to recover heat from the process stream. In a preferred embodiment of the invention, the heat sink liquid comprises the reactants that are fed to a reactor, and the low temperature process stream is the reaction effluent from the reactor.

Abstract: A novel dehydrogenation process is disclosed. This process comprises contacting dehydrogenatable hydrocarbons with a catalytic composite comprising a platinum component, a tin component, a potassium component, a lithium component, and an alumina support, wherein the lithium to potassium atomic ratio of said catalytic composite is in the range of from 3:1 to 5:1. The process of the invention has particular utility for the dehydrogenation of C.sub.3 -C.sub.30 paraffins.

Abstract: Vinyl aromatic compounds are stabilized against undesired polymerization by adding to the vinyl aromatic compounds small amounts of mixtures of alkyl-substituted p-nitrosophenols and p-nitrosophenol.

Abstract: Vinyl aromatic compounds are stabilized against undesired polymerization by adding to the vinyl aromatic compounds small amounts of a N,N-dialkylhydroxylamine and an alkyl benzene sulfonic acid.

Abstract: Unsaturated hydrocarbons may be prepared by subjecting dehydrogenatable hydrocarbon to dehydrogenation in the presence of a dehydrogenation catalyst. The effluent stream from this step, comprising unconverted hydrocarbons, dehydrogenated hydrocarbons, hydrogen and steam, may then be passed to a selective oxidation step in which the hydrogen is selectively oxidized in the presence of an oxygen-containing gas to the substantial exclusion of the oxidation of the hydrocarbons. The oxidation catalyst which is employed will comprise a Group VIII noble metal, a Group IVA metal and a Group IA or IIA metal composited on a metal oxide support. The metal oxide support such as alumina will possess a particular configuration such as a polylobular particle containing from 3 to about 8 lobes and having a ratio of exterior surface to catalyst volume greater than [4D+2L] in which D is the largest representative diameter and L is the length of the particle.

Abstract: An improved process for the production of styrene through dehydrogenation of ethylbenzene in the presence of steam at elevated temperatures, comprising (1) recovering heat of condensation normally lost during separation of the various components of the dehydrogenation reaction effluent, especially of ethylbenzene from styrene, without need or use of a compressor and (2) using such heat to vaporize an aqueous feed mixture of ethylbenzene and dilution water that is introduced into the dehydrogenation reactor, preferably at about atmospheric pressure, thereby obviating the need to use steam to vaporize the liquid ethylbenzene feed and also enabling much of the diluent steam needed as sensible heat for the dehydrogenation reaction to be generated from water.

Abstract: An improved electrical insulating oil which is stable in refining treatment and good electrical properties are maintained under high temperature conditions, and oil-filled electrical appliances impregnated therewith. The electrical insulating oil comprises 1,1,-diarylalkenes which are represented by the following general formula (I): ##STR1## wherein R.sub.1 to R.sub.4 's are the same or different and each of them is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and m and n are integers from 0 to 3, inclusive.

Abstract: The present invention provides a process for distillation of styrenes which can be stably operated without loss of energy saving effect, by leading a part or all of low boiling point component vapor from the top to a compressor to use as a heat source for a reboiler and returning the low boiling point components condensed in the reboiler or a mixture of the condensate and a part of the uncondensed vapor to a recycling line of a distillation column.

Abstract: Para-ethyltoluene dehydrogenation catalyst compositions and processes for using such catalysts are provided. The catalyst compositions comprise a catalytically active iron compound, e.g., iron oxide; a potassium catalyst promoter, e.g., potassium carbonate; an optional chromium compound stabilizer, e.g., chromic oxide, a copper compound, e.g., copper chromite, and a zinc compound, e.g., zinc ferrate. Utilization of particular amounts of zinc ferrate and copper chromite in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the highly selective dehydrogenation of para-ethyltoluene to form para-methylstyrene with excellent conversion.

Abstract: Ethyltoluene is oxidatively dehydrogenated to methylstyrene selectivity and in high conversions by treatment with hydrogen sulfide and oxygen at elevated temperatures of about 450.degree. C. to 700.degree. C. over magnesium oxide catalyst.

Abstract: A process for preparing vinyltoluene comprising passing ethyltoluene through a dehydrogenation zone to form vaporous crude vinyltoluene, adding from about 50 to about 100 parts per million by weight of a polymerization inhibitor such as a nitrated phenol to the vaporous crude vinyltoluene at a temperature between about 200.degree. and about 300.degree. C., condensing the vaporous crude vinyltoluene, maintaining the pH of the aqueous phase of the condensed crude vinyltoluene at a value between about 5.5 and about 6.

Abstract: Titanium-containing molecular sieves are disclosed having use as molecular sieves and as catalyst compositions in hydrocarbon conversion and other processes. The instant invention employs novel titanium-containing molecular sieves comprising titanium, aluminum, phosphorus and oxygen and are generally employable in hydrocarbon conversion processes, including cracking, hydrocracking and hydrotreating.

Abstract: A method for producing an alkenylbenzene by catalytically dehydrogenating an alkylbenzene non-oxidatively in the presence of steam in the reaction zone comprising a fixed-bed of potassium-containing dehydrogenation catalyst particles, wherein the potassium-containing dehydrogenation catalyst particles are prevented from powdering by (a) using a fixed-bed comprising particles of at least two kinds of potassium-containing dehydrogenation catalyst with respectively different potassium contents and (b) arranging the catalyst particles so that those with higher potassium content are not disposed on the inlet side of said catalyst bed with respect to the reaction.

Abstract: A process for producing styrene by the dehydrogenation of ethyl benzene whereby the ethyl benzene in a mixture with steam is introduced into a tubular reactor, the tubes of which are heated by molten salts. The structural parameters of this process are the tube diameter which should be 20 to 35 millimeters, the temperature of the molten salts which should be 580.degree. to 660.degree. C. and at most 20.degree. C. higher than the reaction temperature at the catalyst and the weight ratio of steam to ethyl benzene of the feed stock which should be 0.5 to 1. The process saves energy and increases efficiency by reducing the steam consumption.

Abstract: Single-stage thermolysis of C.sub.8 and C.sub.9 aromatics at temperatures in excess of 900.degree. C. and pressures of less than 0.2 torr or in the presence of steam in excess of 800.degree. C., in the absence of catalysts yields styrene and/or p-methylstyrene in high yields, providing a process for the conversion of xylenes and p-ethyltoluene to preferred styrene monomers.

Abstract: Diisopropenylbenzene is a monomer that can be used in the preparation of many useful polymers and is also a chemical intermediate that can be employed in a number of chemical processes. Diisopropenylbenzene is normally synthesized by the dehydrogenation of diisopropylbenzene. Unfortunately in this dehydrogenation process a number of olefinic impurities are produced as by-products. This invention discloses a process for the separation of diisopropenylbenzene from these impurities and for recycling some of the impurities.

Abstract: A process is provided for conducting organic compound conversion over a catalyst comprising a high silica crystalline zeolite which has been treated by contact with aluminum chloride vapor.

Abstract: Disclosed is a catalyst for the oxidative dimerization of toluene, comprising a composition represented by the general formula:Tl.sub.l M.sub.a M'.sub.b O.sub.cwhereinM represents at least one element selected from the group consisting of beryllium, magnesium, calcium, strontium and barium; M' represents at least one element selected from the group consisting of lithium, sodium, potassium, rubidium, cesium, scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, titanium, zirconium, hafnium, niobium, tantalum, zinc, aluminum, gallium, indium and antimony;a is 0.05 to 15;b is 0.

Abstract: A process is provided for conducting organic compound conversion over a catalyst composition comprising a specially treated crystalline zeolite having a high initial silica-to-alumina mole ratio, said zeolite having been synthesized from a reaction mixture comprising a diamine as a cation source. The treatment of the zeolite material comprises the sequential steps of reacting the zeolite with a dilute hydrogen fluoride solution, contacting the hydrogen fluoride solution reacted material with aluminum chloride vapor, and then treating the aluminum chloride contacted material to convert it to hydrogen form.

Abstract: An apparatus for preparing vinyltoluene comprising passing ethyltoluene through a dehydrogenation zone to form vaporous crude vinyltoluene, adding from about 50 to about 100 parts per million by weight of a polymerization inhibitor such as a nitrated phenol to the vaporous crude vinyltoluene at a temperature between about 200.degree. and about 300.degree. C., condensing the vaporous crude vinyltoluene, maintaining the pH of the aqueous phase of the condensed crude vinyltoluene at a value between about 5.5 and about 6.

Abstract: A process for preparing a metal oxygen composition capable of dehydrocoupling toluene wherein metal oxides such as Sb.sub.2 O.sub.3, PbO, and Bi.sub.2 O.sub.3 are admixed with an organic media such as isobutanol and heated to form a metal oxygen precursor composition which is recovered and calcined is disclosed.

Abstract: Dehydrogenatable hydrocarbons may be subjected to a dehydrogenation reaction in which the hydrocarbons are treated with a dehydrogenation catalyst such as a modified iron compound in the presence of steam in a multi-catalyst bed system. The reaction mixture containing unconverted hydrocarbon, dehydrogenated hydrocarbon, hydrogen and steam is then contacted with a selective oxidation catalyst such as a noble metal of Group VIII of the Periodic Table, a metal of Group IVA of the Periodic Table and, if so desired, a metal of Group IA or IIA of the Periodic Table composited on a highly porous inorganic support. The oxidation catalyst will selectively oxidize the hydrogen to improve the combustion thereof and supply the necessary heat required for a subsequent dehydrogenation treatment.

Abstract: A process for the production of vinyltoluene, comprising the steps of: producing a crude vinyltoluene product by the catalytic dehydrogenation of ethyltoluene; removing compounds from the crude vinyltoluene product which have a higher molecular weight than vinyltoluene to form a prepurified crude vinyltoluene product; and fractionally distilling the prepurified crude vinyltoluene product in a distillation apparatus to recover purified vinyltoluene. The higher molecular weight compounds removed are compounds which foster the conversion of vinyltoluene into cross-linked polymer. The compounds removed preferably have more than 11 carbon atoms. In one embodiment, the step of removing higher molecular weight compounds comprises condensing a vaporous crude vinyltoluene product to form a crude vinyltoluene solution, and subjecting the crude vinyltoluene solution to flash distillation to form a vaporous prepurified crude vinyltoluene product.

Abstract: In the catalytic dehydrogenation of p-ethyltoluene to p-methylstyrene, popcorn polymer forms and builds up in the condenser, shortly plugging it. This is prevented by adding minor amounts of H.sub.2 S continuously to the gaseous product effluent entering the condenser.

Abstract: The invention relates to a process for oxidatively dehydrogenating dehydrogenatable organic compounds to prepare styrene. In this process, the compounds mentioned are reacted in the vapor phase with oxygen at a temperature above 350.degree. C. in the presence of a catalyst based on zirconium phosphate. Suitable dehydrogenatable organic compounds are above all saturated alkylaromatics, in particular ethylbenzene.

Abstract: 4-Vinylcyclohexene-1 is converted to ethylbenzene by contacting the vinylcyclohexene at a temperature ranging from about 100.degree. C. to about 450.degree. C. with a catalyst prepared by impregnating an alumina with an oxide or decomposable salt of Na, K, Rb, Cs, Ca, Sr and/or Ba and calcining the impregnated material at a temperature ranging from about 450.degree. C. to about 750.degree. C.

Abstract: There is disclosed a process for the conversion of terpenes to .alpha.-methyl-methylstyrenes and cymenes which comprises contacting at least one terpene, selected from the group comprised of mono- and bi-cyclic unsaturated hydrocarbons having the formula C.sub.10 H.sub.16 ; with an alkali metal hydroxide catalyst on a support at a temperature of 300.degree. to 500.degree. C.

Abstract: The catalytic dehydrogenation of at least one dehydrogenatable organic compound which has at least one ##STR1## grouping is carried out in the presence of a zinc silicate catalyst and in the substantial absence of free oxygen.

Abstract: A method for the production of ethylbenzene by catalytic dehydrogenation of cycloolefins having 8 carbon atoms and two double bonds which is present in a styrene stream. The method is carried out at a temperature from about 160.degree. C. to about 450.degree. C. by passing the stream over an alkali metal complex catalyst.

Abstract: Vinyl cyclohexene is converted to ethylbenzene and styrene at 170.degree. C.-360.degree. C. in the presence of a hydrogen transfer catalyst typified by IrCl(CO)(Ph.sub.3 P).sub.2.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at hydrocarbon dehydrogenation conditions, with a novel attenuated superactive multimetallic catalytic composite comprising a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of a platinum group component maintained in the elemental metallic state, and of a manganese component. An example of the attenuated superactive nonacidic multimetallic catalytic composite disclosed herein is a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of an alkali or alkaline earth component, a manganese component, and of a platinum group component which is maintained in the elemental metallic state during the incorporation of a rhenium carbonyl component.

Abstract: A method to synthesize styrene from toluene by: (a) oxidizing toluene to form oxygenated toluene derivatives; (b) carbonylating said oxygenated products in the presence of a carbonylation catalyst and preferably a halogen promoter to produce phenylacetic acid; (c) hydrogenating said phenylacetic acid to synthesize phenylethyl alcohol; and (d) dehydrating said phenylethyl alcohol to obtain a high yield of styrene.

Abstract: Alkylaromatic hydrocarbons are dehydrogenated in admixture with steam, with the dehydrogenation zone effluent being condensed to form a water stream which is purified in a stripping column. The stripping column is reboiled by indirect heat exchange against the effluent of the dehydrogenation zone. The steam-rich overhead vapor stream of the stripping column is mixed directly into the dehydrogenation zone feed stream without intermediate condensation or pressurization.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them at dehydrogenation conditions in the presence of a complex oxide catalyst comprising molybdenum, copper and tin and at least one element selected from the group consisting of Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Th and U. For example, an alkyl aromatic hydrocarbon, e.g. ethylbenzene, can be dehydrogenated to an alkenyl aromatic hydrocarbon, e.g. styrene, in the presence of an oxide complex catalyst comprising molybdenum, copper, tin and at least one element selected from the group consisting of K, Cs, Ba, Mg and Ca.

Abstract: Aniline may be prepared by reaction of nitrobenzene and vinylcyclohexene at 170.degree. C.-300.degree. C., typically 200.degree. C., in the presence of a homogeneous catalyst typified by IrCl(CO)(Ph.sub.3 P).sub.2.

Abstract: A palladium or palladium alloy hydrogen diffusion membrane which has been treated with silane and/or silicon tetrafluoride is employed to separate hydrogen from a hydrocarbon with which it is in admixture and from which it may have been produced under dehydrogenation conditions in the presence of said membrane.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at hydrocarbon dehydrogenation conditions, with a novel attenuated superactive multimetallic catalytic composite comprising a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of a platinum group component maintained in the elemental metallic state, and of a cadmium component. An example of the attenuated superactive nonacidic multimetallic catalytic composite disclosed herein is a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of an alkali or alkaline earth component, a cadmium component, and of a platinum group component which is maintained in the elemental metallic state during the incorporation of a rhenium carbonyl component.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at hydrocarbon dehydrogenation conditions, with a novel attenuated superactive multimetallic catalytic composite comprising a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of a platinum group component maintained in the elemental metallic state, and of a germanium component. An example of the attenuated superactive nonacidic multimetallic catalytic composite disclosed herein is a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of an alkali or alkaline earth component, a germanium component, and of a platinum group component which is maintained in the elemental metallic state during the incorporation of the rhenium carbonyl component.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at dehydrogenation conditions, with a nonacidic catalytic composite comprising a combination of catalytically effective amounts of a platinum group component, a cobalt component, a tantalum component, and an alkali or alkaline earth component with a porous carrier material in amounts sufficient to result in a composite containing, on an elemental basis, about 0.01 to about 2 wt. % platinum group metal, about 0.05 to about 5 wt. % cobalt, about 0.01 to about 5 wt. % tantalum, and about 0.1 to about 5 wt. % alkali metal or alkaline earth metal.

Abstract: The invention relates to a process of converting ethylbenzene to styrene by catalytic dehydrogenation at temperatures of about 600.degree. C. in the presence of water vapor in a tubular reactor. The heat required for the dehydrogenation is fed to the tubular reactor with a molten salt bath. The dehydrogenation is effected isothermally and in a single stage under atmospheric pressure or preferable under a subatmospheric pressure with a water vapor-ethylbenzene ratio of 1.2 to 1.5 kg of water vapor per kg of ethylbenzene. The temperature of the ethylbenzene-water-vapor mixture entering the tubular reactor is maintained 50.degree. to 100.degree. C. below the temperature of the molten salt bath.

Abstract: A catalyst having a noble metal of Group 8 of the Periodic Table of Elements carried on aluminum sponge and a method for the dehydrogenation of cyclohexanes which comprises bringing cyclohexanes, in a heated state, into contact with the catalyst described above in conjunction with hydrogen.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at dehydrogenation conditions, with a nonacidic catalytic composite comprising a combination of catalytically effective amounts of platinum group component, a cobalt component, a cadmium component, and an alkali or alkaline earth component with a porous carrier material in amounts sufficient to result in a composite containing, on an elemental basis, about 0.01 to about 2 wt. % platinum group metal, about 0.05 to about 5 wt. % cobalt, about 0.01 to about 5 wt. % cadmium and about 0.1 to about 5 wt. % alkali metal or alkaline earth metal.

Abstract: A catalyst having a noble metal of Group 8 of the Periodic Table of Elements carried on aluminum sponge and a method for the dehydrogenation of cyclohexanes which comprises bringing cyclohexanes, in a heated state, into contact with the catalyst described above in conjunction with hydrogen.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at dehydrogenation conditions, with a catalytic composite comprising a combination of catalytically effective amounts of a platinum group component, a cobalt component, and a zinc component with a porous carrier material. A specific example of the nonacidic catalytic composite disclosed herein is a combination of a platinum group component, a cobalt component, a zinc component, and an alkali or alkaline earth component with a porous carrier material in amounts sufficient to result in a composite containing about 0.01 to about 2 wt. % platinum group metal, about 0.05 to about 5 wt. % cobalt, about 0.01 to about 5 wt. % zinc and about 0.1 to about 5 wt. % alkali metal or alkaline earth metal.

Abstract: Dehydrogenatable hydrocarbons are dehydrogenated by contacting them, at hydrocarbon dehydrogenation conditions, with a novel superactive multimetallic catalytic composite comprising a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of a catalytically effective amount of a platinum group component maintained in the elemental metallic state. An example of the superactive nonacidic multimetallic catalytic composite disclosed herein is a combination of a catalytically effective amount of a pyrolyzed rhenium carbonyl component with a porous carrier material containing a uniform dispersion of catalytically effective amounts of an alkali or alkaline earth component and of a platinum group component which is maintained in the elemental metallic state during the incorporation of the rhenium carbonyl component.