Abstract: In a process for preparing essentially unbranched oligomers of alkenes having from 4 to 6 carbon atoms starting from the alkenes or a hydrocarbon stream comprising such alkenes over a nickel-containing heterogeneous catalyst in an adiabatically operated reactor at from 20 to 300° C. and pressures of from 1 to 100 bar, a first substream of the output from the reactor is worked up to isolate the oligomers and the second substream is recirculated together with fresh alkene or a fresh hydrocarbon stream comprising such alkenes to the reactor.

Abstract: A process for oligomerising olefins in an organic feed containing at least one olefin comprises two steps with different types of catalysis. The cut to be treated containing at least one olefin (Cn) is introduced via line 1 into a reaction zone R1 where in a first step it undergoes catalytic oligomerisation, either of a liquid phase homogeneous type, or heterogeneous with a solid support. The effluent produced is sent via line 2 to a heat exchanger E1 traversed by a cold liquid. The effluent is thus cooled before being sent via line 3 to a second reaction zone R2 where it undergoes catalytic oligomerisation in a liquid-liquid two-phase medium. After reaction, the effluent is fed via line 4 to a zone L1 where it is washed. After washing, the hydrocarbon fraction is sent via line 5 to separator S1.

Abstract: The mixture described is a mixture of isomeric nonanol diesters of a dicarboxylic acid, selected from the class consisting of a mixture of diesters of adipic acid in the 1H NMR spectrum of which, observed in CDCl3, the ratio of the area under the resonance signals at chemical shifts in the range from 1.0 to 2.0 ppm with respect to TMS to the area under the resonance signals at chemical shifts in the range from 0.5 to 1.0 ppm with respect to TMS is from 1.20 to 5.00 and a mixture of diesters of phthalic acid, in the 1H NMR spectrum of which, observed in CDCl3, the ratio of the area under the resonance signals at chemical shifts in the range from 1.1 to 3.0 ppm with respect to TMS to the area under the resonance signals at chemical shifts in the range from 0.5 to 1.1 ppm with respect to TMS is from 1.00 to 4.00.

Abstract: Ethylene is oligomerized with certain catalysts based on iron and cobalt complexes of 2,6-pyridinecarboxaldehydebis(imine) and 2,6-diacylpyridine-bis(imine) tridentate ligands.

Abstract: In a process for the oligomerization of light olefins (e.g. propylene) to more valuable higher olefins (e.g. hexene), the use of a molecular sieve (e.g. SAPO-11) that has been acid washed has shown to provide superior selectivity to, and yield of, the desired product. These benefits are attributed to a reduction in non-selective acid sites as well as an increase in phosphorous content (in the case of SAPO molecular sieves) at the molecular sieve crystallite surface, a probable result of removing amorphous silicon aluminum phosphate acid, silicophosphorous acids, and/or phosphoric acids. Furthermore, this removal is likely accompanied by an increased accessibility of olefinic feed components to the so-called “selective” acid sites within the sieve pores. Post-synthesis acid washing of the molecular sieve has not only demonstrated a narrower carbon number distribution of olefin oligomers, but also improved the linearity of the oligomerized olefinic product slate in general.

Abstract: A process for preparing halogen-free, reactive polyisobutene having a terminal double bond content of more than 60 mol % and an average molecular weight Mn of 800-3000 dalton by cationic polymerization in the liquid phase of isobutene over an acidic, essentially halogen-free heterogeneous catalyst, where a) a hydrocarbon mixture of essentially C4-hydrocarbons comprising isobutene in an amount of from 10 to 80% by weight is used as the starting material and b) polymerization is carried out continuously at from −30 to 0° C. with average starting material residence times of one hour or less, where the temperature and the residence time are selected such that the isobutene conversion is less than 60% and, after separation from the resulting polyisobutene, the isobutene is either enriched in the partially converted hydrocarbon mixture and returned to the polymerization or passed to another isobutene reaction coupled with the polymerization.

Abstract: In a process for the hydroformylation of olefins having from 12 to 100 carbon atoms in the presence of a cobalt carbonyl catalyst at pressures of from 100 to 400 bar and at from 100 to 200° C., depressurization and recovery of the cobalt catalyst by extraction with an aqueous acid solution in the presence of atmospheric oxygen, (a) the extraction is carried out in the presence of a polymeric emulsion breaker selected from the group consisting of alkoxylated compounds containing amino, imino or OH groups, and (b) to achieve complete phase separation in the organic phase still containing small amounts of aqueous phase, the formation of relatively large droplets of the dispersed aqueous phase is effected in a coalescence stage.

Abstract: A process for making a lube base stock wherein an olefinic feedstock is contacted with an oligomerization catalyst in a catalytic distillation unit to produce a product having a higher number average molecular weight than the olefinic feedstock. That product is separated zone in the catalytic distillation unit into a light byproduct fraction and a heavy product fraction that includes hydrocarbons in a lube base stock range.

Abstract: A process for making a lube base stock wherein an olefinic feedstock is separated into a light olefin fraction and a medium olefin fraction. The light olefin fraction is contacted with a first oligomerization catalyst in a first oligomerization zone to produce a first product. Both the medium olefin fraction and the first product are contacted with a second oligomerization catalyst in a second oligomerization zone to produce a second product. The second product is separated into a light byproduct fraction and a heavy product fraction that includes hydrocarbons in the lube base stock range.

Abstract: A catalyst and a process are provided for oligomerizing ethylene. A heterogeneous catalyst system comprises: (1) a chelating ligand, preferably 2-diphenyl phosphino benzoic acid (DPPBA); (2) a nickel precursor, preferably nickel chloride hexahydrate (NiCl2.6H2O); (3) a catalyst activator, preferably sodium tetraphenylborate (NaBPh4); and (4) silica. A 1:1:1 molar ratio of Ni:DPPBA:BPh4 catalyst components are fixed on a silica support using low-temperature fixation. The catalyst components are dispersed in a diluent, preferably ethanol, and silica is added. The ethanol is evaporated using freeze-drying equipment to form a silica-supported catalyst system. The silica-supported catalyst is slurried in ethanol in a reactor, and ethylene is added. The reactor pressure and temperature are maintained at about 725 psig and 100° C., respectively, for about two hours.

Abstract: Propylene may be oligomerized by contact with cobalt complexes corresponding to the following structure: ##STR1## wherein R.sup.1 -R.sup.7 are hydrogen, hydrocarbyl or inert functional groups, and X is an anion. The resulting olefins are useful as chemical intermediates.

Abstract: Catalysts and processes are described to make low molecular weight, essentially terminally-unsaturated, viscous poly(1-olefin) or copoly(1-olefin) having a high terminal vinylidine content from a feed stock containing one or more 1-olefin and other volatile hydrocarbon liquids using a Ziegler catalyst made from a Group IVb metallocene and an aluminoxane cocatalyst, particularly bis(cyclopentadienyl) and bis(indenyl) titanium(IV), zirconium(IV) or hafnium(IV) compounds and methylaluminoxane. A particularly useful feed stock is a refinery stream containing 1-olefins and isobutylene which is used to make polyisobutylene.

Abstract: The invention concerns NU-88 zeolite, characterized by:i) a chemical composition with the following formula, expressed in terms of the mole ratios of the oxides for the anhydrous state:100 XO.sub.2, mY.sub.2 O.sub.3, pR.sub.2/n Owherem is 10 or less;p is 20 or less;R represents one or more cations with valency n;X represents silicon and/or germanium;Y represents one or more of the following elements: aluminium, iron, gallium, boron, titanium, vanadium, zirconium, molybdenum, arsenic, antimony, chromium and manganese; andii) an X ray diffraction diagram, in its as synthesized state, which comprises the results shown in Table 1 of the description.The invention also concerns the preparation of the zeolite, any catalyst containing the zeolite and any catalytic process using such a catalyst.

Abstract: A process for the preparation of halogen-free, reactive polyisobutene having a content of terminal double bonds of more than 50 mol % and an average molecular weight M.sub.n of from 500 to 5000 dalton by the cationic polymerization of isobutene or isobutene-containing hydrocarbon mixtures in the liquid phase, wherein the polymerization is carried out at a temperature of from -30.degree. to +40.degree. C. over a heterogeneous polymerization catalyst containing at least one element acting as promoter and selected from Group IB, Group IIB, Group IIIB, Group IVB, Group VB, Group VIIB, or Group VIIIB of the Periodic Table or from Group IIA, Group IIIA, Group IVA, Group VA, or Group VIA of the Periodic Table or a number of said elements in each case in the form of an oxygen-containing compound and zirconium in the form of an oxygen-containing compound, said polymerization catalyst containing no industrially effective amounts of halogens.

Abstract: A process is provided to trimerize or oligomerize olefins in the presence of an olefin oligomerization catalyst and a solvent which is a product of the olefin oligomerization process.

Abstract: A catalyst for oxidative coupling of methane comprising Fe.sub.2 O.sub.3 deposited on a silica substrate, said silica substrate having particle sizes in the range of about 150 to 215 .mu.m, and a method for producing said catalyst in which particles of Fe.sub.2 O.sub.3, with a particle size in the range from 100 to 150 .mu.m, and particles of silica, with a particle size in the range from about 150 to about 215 .mu.m are mixed together. The particles are heated to a temperature of at least about 800.degree. C., after which the silica particles impregnated with Fe.sub.2 O.sub.3 are separated from the remaining iron particles.

Abstract: Straight-chain C.sub.2 -C.sub.6 -olefins are oligomerized to their dimers, trimers and tetramers by means of a fixed-bed catalyst, at superatmospheric pressure and at room temperature or elevated temperatures, by a process in which the catalyst used is one which contains, as active components, after deduction of the loss on ignition following heating at 900.degree. C., from 10 to 70% by weight of nickel oxide, calculated as NiO, from 5 to 30% by weight of titanium dioxide or zirconium dioxide, from 0 to 20% by weight of alumina, from 20 to 40% by weight of silica and from 0.01 to 1% by weight of an alkali metal oxide, with the proviso that the contents of the individual components in the catalyst sum to 100% by weight.

Abstract: Ethylene is effectively oligomerized to linear alpha-olefins using catalyst systems based on transition metal compounds. It has been found that when the reaction is conducted in a polar organic liquid as solvent, incorporation of water into the solvent at levels of 1 to 10 weight percent increases alpha-olefin purity and also influences the Schulz-Flory distribution.

Abstract: An oligomerization catalyst according to the invention comprises a nickel compound (A); an organophosphoric compound (B); an organoaluminum compound (C); and a compound of the group consisting of carbon-halogen bond-containing compounds, oxoacid and salts thereof, sulfonic acid and derivatives thereof, and compounds of any of the formulae QX.sup.4.sub.n, QR.sub.n, QR'.sub.n, QX.sup.4.sub.1 R.sub.m, QX.sup.4.sub.1 R'.sub.m, QR.sub.1 R'.sub.m, Q.sup.1 (BR.sub.4).sub.p and R"(BR.sub.4) wherein Q is an element of the group consisting of Mg, Ti, Zr, B and Sn, Q.sup.1 is an element of the group consisting of Li, Na, K, Ca and Zn, X.sup.4 is a halogen or hydrogen atom, R is a C.sub.1 -C.sub.12 hydrocarbon group, R' is a C.sub.1 -C.sub.12 oxygen-containing hydrocarbon group, R" is a C.sub.1 -C.sub.20 hydrocarbon group or an ammonium group, n is a valence of Q, l, m is a natural member that satisfied n=l+m, and p is a valence of Q.sup.1. This catalyst is useful for the production of alpha-olefinic oligomers.

Abstract: Hydrocarbon conversion processes, e.g., alkylation, are disclosed and claimed which use as the catalyst novel fluoride containing substituted smectite clays. The clay has the formulaA.sub.x (M.sub.y M'.sub.4-y)(Si.sub.8-x M.sub.t M'.sub.v)O.sub.20 (OH).sub.4-u F.sub.uwhere A is a cation, M and M' are metals having a +3 oxidation state, each selected from the group consisting of aluminum, gallium, iron and chromium, x is the moles of A, y is the moles of M, t and v are the moles of M and M' in the tetrahedral layer and t+v=x and u is the moles of F. The clay composition may be used as is or after pillaring to catalyze hydrocarbon conversion processes such as alkylation.

Abstract: This invention relates to a process for the converting ethylene to a mixture of 1-olefins by (a) feeding ethylene through an oligomerization catalyst bed to form an oligomer predominating in C2-C6 olefins and (b) feeding the oligomer, optionally admixed with fresh ethylene, containing at least 50% by volume ethylene, through a metathesis catalyst bed to form a product predominating in C2-C6 1-olefins. Steps (a) and (b) can be carried out sequentially and in a single reactor under the same conditions of reaction temperature and pressure. This mitigates the perceived disadvantages of low activity and low conversions of relatively inexpensive oligomerization catalysts and forms oligomer having the desired distribution of 1-olefin components for use as comonomer in a polyolefin process.

Abstract: A novel catalytic composition comprises a mixture of lithium halide, a hydrocarbylaluminium halide and at least one compound of a catalytic element, in particular a nickel complex. The invention also concerns a process for the oligomerisation and co-oligomerisation of olefins catalysed by said composition. The catalytic mixture, which is liquid at the start of the reaction, is gradually transformed into a solid which is then readily separated from the reaction products.

Abstract: In a process for the oligomerization of C.sub.2 -C.sub.12 -alkenes, an alkene-containing feedstock having a water content of from 0.05 to 0.25 molar %, based on the hydrocarbon content of the feedstock, is passed over a zeolite catalyst. Improved alkene conversion and catalyst life are obtained compared to processes in which non-hydrated feedstocks are used.

Abstract: A method includes organic homologation employing an organic-containing feed. The organic-containing feed is directed into a molten metal bath. The molten metal bath includes a metal which can cause an organic component of the organic-containing feed to homologate and form a homologated organic compound. Operating conditions are established and maintained in the reactor to cause the organic component to form a homologated organic compound that is discharged from the molten metal bath.

Abstract: A supported catalyst component for an olefin polymerization catalyst comprising a solid particulate support, a magnesium halide, and optionally a Group 4 or 5 transition metal compound, a Group 2 or 13 organometal compound, and an electron donor, wherein a majority of particles of the solid particulate support is in the form of an agglomerate of subparticles. A process for preparing this supported catalyst component. A catalyst composition comprising this catalyst component and a cocatalyst. An olefin polymerization process using such a catalyst composition.

Abstract: An amorphous, micro/mesoporous silica-alumina gel with controlled pore size, having a surface area of at least 500 m.sup.2 /g and with a molar ratio of SiO.sub.2 :Al.sub.2 O.sub.3 of at least 30:1, is prepared by hydrolysing and causing a tetra-alkyl ammonium hydroxide, an aluminum trialkoxide, and a tetra-alkyl orthosilicate to gelate, by operating at a temperature equal to, or higher than, the boiling temperature, under atmospheric pressure, of any alcohols which are developed as a by-product from said hydrolysis reaction, without said alcohols being removed, or being substantially removed, from the reaction media; and the so produced gel being dried and fired. So obtained gel is an active catalyst in hydrocarbon conversion reactions, in particular in light olefin isomerization and oligomerization processes, e.g., in propylene oligomerization processes to yield useful liquid hydrocarbons for gasoline and jet fuel formulation.

Abstract: There is provided a catalytic oligomerization process. The process involves the use of a catalyst comprising an acidic solid. The acidic solid may comprise a Group IVB metal oxide, such as zirconia, modified with an oxyanion of a Group VIB metal, such as tungsten. The oligomers produced by this process may be hydrogenated to produce thermally stable lubricants and lubricant additives, gasoline and diesel.

Abstract: The present invention relates to the oligomerization of lower alpha olefins, and particularly ethylene, to higher olefins in the presence of a catalyst precursor having either or both of a dithiophosphinate complex and a heterobifunctional ligand having a phosphine center and an imine or similar center, in the presence of an activator. The catalysts have a high reactivity and a good selectivity.

Abstract: The present invention relates to a catalyst suitable for oligomerization of olefins which is prepared by a process which comprises reacting a catalyst precursor ligand having a formula ##STR1## wherein R.sub.1 and R.sub.2 each independently is an alkyl, alkoxy, aryl, or aryloxy group having from about 1 to about 20 carbon atoms, with the proviso that R.sub.1 and R.sub.2 are not both aryl, or R.sub.1 and R.sub.2 together form a divalent hydrocarbon moiety, and X is 1,2-arylene, O-CH.sub.2, S-CH.sub.2, or Se-CH.sub.2 with a deprotonation source, a transition metal compound and a catalyst activator. The invention further relates to an oligomerization process utilizing this catalyst.

Abstract: The invention relates to a process for the dimerization of a conjugated diene using an iron triad metal nitrosyl halide, in combination with a reducing agent, as catalyst. The process is characterized in that the dimerization is carried out in the presence of nitrogen monoxide (NO). The invention is of interest in particular for the dimerization of butadiene to 4-vinyl cyclohexene.

Abstract: Polymeric fuels are produced from saturated C.sub.4 hydrocarbons by a process comprising:(A) dehydroisomerizing a gas mixture comprising predominantly of n-butane and hydrogen in a catalytic reactor containing a catalyst (a) of platinum supported on alumina, whose surface is coated with silica, and, optionally, a solid acidic catalyst (b) selected from the group consisting of alumina, whose surface is coated with silica, and Boralite B, with an effluent being obtained which comprises a mixture of predominantly of unreacted n-butane, butenes and isobutene, all of which components of the mixture have a carbon atom content less than 5;(B) separating the mixture of olefins and parafins from hydrogen and aromatic byproducts; and(C) oligomerizing said mixture in the presence of a catalyst consisting of amorphous silica-alumina gel, as determined by X-rays, having a silica:alumina molar ratio within the range of 30:1 to 500:1, with a surface area of from 500 to 1000 m.sup.

Abstract: There is provided an oligomerization process. The process involves the use of a catalyst comprising an acidic solid. The acidic solid may comprise a Group IVB metal oxide, such as zirconia, modified with an oxyanion of a Group VIB metal, such as tungsten. The oligomers produced by this process may be hydrogenated to produce thermally stable lubricants and lubricant additives.

Abstract: The invention provides a two-step process for converting cyclopentadiene dimer to a high density fuel mixture comprising the steps of:(a) reacting said cyclopentadiene dimer in the presence of a solid catalyst comprising a porous crystalline material having a Constraint Index of from about 0.1 to about 12 under oligomerization/isomerization conditions to convert at least a portion of said cyclopentadiene dimer to a normally liquid intermediate product containing cyclopentadiene trimer, cyclopentadiene tetramer, and the isomerized and oligomerized products derived from the reaction of at least three cyclopentadiene monomer units;(b) hydrogenating said normally liquid intermediate product of step (a) in the presence of a hydrogenation catalyst to form a normally liquid high energy density fuel.

Abstract: This invention relates to a process for the production of lubricating oils having a viscosity index of at least 120 and a pour point of at least -45.degree. C. by (a) oligomerizing a mixture of C5-C20 1-olefins comprising at least 2.6% w/w of 1-decene and at least 6% w/w of 1-hexene in the presence of a catalyst. The lubricating oil so formed may be hydrogenated in the presence of hydrogen to improve the oxidation stability thereof. The process is particularly suited to olefins feeds produced during a Fischer-Tropsch synthesis in which carbon monoxide and hydrogen are passed over a heated catalyst.

Abstract: There is provided a catalyst comprising nickel supported on a pillared (e.g., silica pillared) vacancy titanate material. There is also provided a method for preparing this catalyst. This method may involve impregnating a pillared vacancy titanate material with a nickel nitrate solution. There is further provided a process for oligomerizing ethylene using this catalyst.

Abstract: A method of producing an oxidative coupling catalyst is disclosed by mixing particles of Fe.sub.2 O.sub.3, with a particle size in the range from 100 to 150 .mu.m, and silica, with a particle size in the range from about 150 to about 215 .mu.m. The particles are heated to a temperature of at least about 800.degree. C., after which the silica particles impregnated with Fe.sub.2 O.sub.3 are separated from the remaining iron particles. The catalyst can be utilized for the oxidative coupling of methane with water molecules on the surface of the silica substrate, with the silica having a particle size in the range from about 150 to about 215.ltoreq..mu.m. The silicate catalyst substrate is essentially non-porous and has an average geometrical surface on the order of about 0.004 .mu.m.sup.2 /g and a surface concentration of iron on the order of about 2% by weight.

Abstract: An ethylene oligomerization process is provided wherein ethylene is contacted with a nickel(II) halide compound, a phosphine compound, and a carboxylate compound in a solvent to produce a precursor reaction mixture, followed by contacting ethylene with the precursor reaction mixture and a borohydride compound to produce a product reaction mixture comprising the desired oligomerization product.

Abstract: An ethylene dimerization process is provided wherein ethylene is contacted with an organocobalt(II) or organocobalt(III) compound and a borohydride compound in a solvent to produce a product reaction mixture comprising a C.sub.4 fraction of predominantly 1-butene. A phosphine compound can additionally be provided in the solvent with an organocobalt(III) compound to enhance selectivity to 1-butene.

Abstract: An ethylene oligomerization process is provided wherein ethylene is contacted with a nickel(II) halide compound, a phosphine compound and a zinc component in a solvent to produce a precursor reaction mixture, followed by contacting ethylene with the precursor reaction mixture and a fluorinated organoacid to produce a product reaction mixture comprising the desired oligomerization product.

Abstract: An ethylene dimerization process is provided wherein ethylene is contacted with an organonickel (0) compound and a phosphine compound in a fluorinated alcohol solvent to produce a precursor reaction mixture, followed by contacting ethylene with the precursor reaction mixture and a fluorinated organoacid to produce a product reaction mixture comprising a C.sub.4 fraction of predominantly 2-butenes.

Abstract: A process is provided for effecting catalytic conversion of an organic compound-containing feedstock to conversion product which comprises contacting said feedstock under catalytic conversion conditions with a catalyst comprising an active form of a functionalized inorganic, porous, non-layered crystalline phase having uniformly sized pores of at least about 13, e.g., at least about 15, Angstrom Units in diameter.

Abstract: The process of the present invention relates to a simplified method for the removal of halogen containing catalytic residues from olefin polymerization products. More specifically, the present invention employs as a treating agent, a quaternary ammonium salt, to facilitate removal of greater than 95% of catalytic residues in a single caustic or water wash with less than 15 minutes of settling time required after the wash.

Abstract: Olefins are oligomerized by passing a hydrocarbon feedstock mixture containing olefins of from 2 to 8 carbon atoms over a molecular sieve having a pore diameter of from greater than 4 angstroms to 15 angstroms, and then oligomerizing said olefins by passing the hydrocarbon feedstock over a nickel-containing catalyst at a temperature of from 0.degree.to 200.degree. C. and at a pressure of from 1 to 70 bar absolute.

Abstract: A crystalline aluminosilicate having its anhydrous state a formula expressed in terms of mol ratios as follows:xQ:0.01-0.1 M.sub.2/n O:0-0.8 Z.sub.2 O.sub.3 :SiO.sub.2 :0.0001-0.5 MeS,wherein:Q is an organic nitrogen compound;Z is aluminium, boron, gallium or mixtures thereof;x is between 0 and 0.5;M is at least one metal cation of valence n; andMe is at least one of the metals which form an insoluble sulfide compound.

Abstract: A non-aqueous liquid composition with an ionic character resulting from the contacting of at least one alkylaluminum dihalide with at least one quaternary ammonium halide and/or at least one quaternary phosphonium halide, said composition being liquid below 80.degree. C., for example, between -70.degree. and +40.degree. C., is useful as a solvent of catalysts for the dimerization, codimerization and oligomerization of olefins.

Abstract: A process is disclosed for preparing functionalized linear olefins by dimerizing terminal olefins in the presence of a cationic rhodium compound. Novel rhodium compounds useful in this process are also disclosed.

Abstract: A process is disclosed for preparing functionalized linear olefins by dimerizing terminal olefins in the presence of a cationic rhodium compound. Novel rhodium compounds useful in this process are also disclosed.

Abstract: The invention concerns a catalytic composition resulting from placing at least one divalent nickel compound into contact with at least one hydrocarbylaluminum halide and at least one epoxy compound, in any order. It also concerns the use of the catalytic composition in a process of oligomerizing monoolefins.

Abstract: The preparation, structure, and properties of solid inorganic materials containing aluminum, boron, oxygen and at least one Group VIII metallo element, selected from the group consisting of cobalt and nickel is described. Also described in the use of such materials in catalytic compositions for the conversion of organic compounds. In particular, the new materials having the general formula:(x) (M.sub.m :M'.sub.n)O.(y)Al.sub.2 O.sub.3.(z)B.sub.2 O.sub.

Abstract: Aluminophosphate molecular sieves substituted with cobalt, manganese or iron and having the AlPO.sub.4 -34 or AlPO.sub.4 -5, or related AlPO.sub.4 structure activate methane starting at approximately 350.degree. C. Between 400.degree. and 500.degree. C. and at methane pressures .ltoreq.1 atmosphere the rate of methane conversion increases steadily with typical conversion efficiencies at 500.degree. C. approaching 50% and selectivity to the production of C.sub.2+ hydrocarbons approaching 100%. The activation mechanism is based on reduction of the transition metal(III) form of the molecular sieve to the transition metal(II) form with accompanying oxidative dehydrogenation of the methane. Reoxidation of the - transition metal(II) form to the transition metal(III) form can be done either chemically (e.g., using O.sub.2) or electrochemically.