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: 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, and a magnesium compound, e.g., magnesium oxide. Utilization of particular amounts of magnesium compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene in improved yields.

Abstract: Hydrocarbons are catalytically dehydrogenated in a reaction zone comprising at least two separate beds of dehydrogenation catalyst. The reactants are reheated and hydrogen is consumed through use of an intermediate bed of hydrogen selective oxidation catalyst. The amount of hydrogen consumed in the combustion step is increased by cooling the effluent of the first dehydrogenation catalyst bed by direct or indirect heat exchange.

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, and a bismuth compound, e.g., bismuth trioxide. Utilization of particular amounts of bismuth compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene in improved yields.

Abstract: Disclosed is the vapor phase catalytic dehydrogenation of indanes to indenes over a Co--Mo oxide on alumina catalyst and in the presence of sulfur.

Abstract: Dehydrogenatable hydrocarbons may be subjected to a dehydrogenation reaction in which the hydrocarbons are treated with a dehydrogenation catalyst comprising a modified iron compound 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 in preference to carbon dioxide and carbon monoxide or hydrocarbons. The selective oxidation of hydrogen will improve the combustion thereof and supply the necessary heat which is required for a subsequent dehydrogenation treatment. The selective oxidation catalyst which is used will comprise a noble metal of Group VIII of the Periodic Table and, if so desired, a metal of Group IA or IIA of the Periodic Table composited on a porous inorganic support. The inorganic support will have been calcined prior to impregnation thereof at a temperature in the range of from about 900.degree.

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: 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, and a calcium compound, e.g., calcium oxide. Utilization of particular amounts of calcium compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene in improved yields.

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: 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, and a bismuth compound, e.g., bismuth trioxide. Utilization of particular amounts of bismuth compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene in improved yields.

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, and a calcium compound, e.g., calcium oxide. Utilization of particular amounts of calcium compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene in improved yields.

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, and a magnesium compound, e.g., magnesium oxide. Utilization of particular amounts of magnesium compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene in improved yields.

Abstract: Catalysts found to be particularly effective in the dehydrogenation of alkyl aromatics, for example ethylbenzene to styrene, where the catalysts include iron oxide, 12 to 30% of an alkali metal compound, 3 to 7% of a cerium compound, 1.5 to 6.0% of a molybdenum compound and 1 to 8% of a calcium compound. Catalyst can also include 0 to 8.0% of a chromium compound.

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, and a gallium compound, e.g., gallium trioxide. Utilization of particular amounts of gallium compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene with sustained catalyst activity, with minimized aromatic ring loss and with minimal formation of popcorn polymer from the reaction effluent.

Abstract: A stabilized heteropoly molybdate catalyst precursor in calcined form and containing anionic molybdenum in defect state is surface impregnated with certain metal cations. The stabilized precursor is one obtained by incorporating into the reaction product of a molybdate and a soluble phosphate, silicate or arsenate, an aqueous chloride ion and a compound of phosphotungstate, silicotungstate, vanadium arsenate, silico-arsenate, phosphovanadate, or silicovanadate, followed by drying and calcining. During the chloride ion stabilization step other metals may be optionally incorporated in forming the stabilized precursor.The obtained precursor is catalytically active in the conversion of the unsaturated aldehydes to the corresponding unsaturated carboxylic acids with or without incorporation of the metal cation during the chloride ion stabilization step.

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, and a gallium compound, e.g., gallium trioxide. Utilization of particular amounts of gallium compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene with sustained catalyst activity, with minimized aromatic ring loss and with minimal formation of popcorn polymer from the reaction effluent. suBACKGROUND OF THE INVENTION1.

Abstract: A method of dehydrogenating alkylaromatic compounds to produce vinylaromatic monomers wherein an alkylaromatic compound feed stream is preheated by passing it in indirect heat exchange relation with steam, the preheated feed stream is then flash vaporized by injecting superheated steam therein, the feed vapors are then passed in indirect heat exchange relation with hot effluent vapors withdrawn from the dehydrogenation reaction zone, after which the hot alkylaromatic compound vapors are introduced, together with superheated steam into a dehydrogenation reaction zone containing a bed of alkylaromatic compound dehydrogenation catalyst and reacted to produce a vinylaromatic compound containing effluent stream which is withdrawn from the reaction zone, passed in heat exchange relation with the incoming alkylaromatic compound feed and condensed.

Abstract: The preparation of a compound of formula R.sup.1 --C(R.sup.2).dbd.CH.sub.2 (R.sup.1 and R.sup.2 are a phenyl, alkyl or alkenyl group or a hydrogen atom) by contacting a mixture of steam and a compound of formula R.sup.1 --C(R.sup.2)(H)--CH.sub.3 at elevated temperature under non-oxidative dehydrogenation conditions with a catalyst having a spinel structure allows lower ratios steam to compound of formula R.sup.1 --C(R.sup.2)(H)--CH.sub.3, a higher selectivity to the compound of formula R.sup.1 --C(R.sup.2).dbd.CH.sub.2 and a lower temperature when lithium is present in the spinel structure.

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: The invention relates to a carrier-supported catalyst comprising oxides of chromium and tungsten and at least one of the oxides of molybdenum and potassium in the atomic ratio of Cr.sub.1 W.sub.0.1-0.5 Mo.sub.0-0.05 K.sub.0-0.5 on a porous carrier material, and to a process for making it.

Abstract: A method for preparing C.sub.3 -C.sub.4 olefins and vinylaromatic compounds, viz. styrene, vinyltoluenes or vinylxylenes which comprises alkylation of toluene or methyl derivatives thereof with a C.sub.2 -C.sub.3 olefin into the methyl group. The resulting alkylaromatic compounds are subjected to conversion to the desired products in the presence of ethylene on a catalyst consisting of chromium oxide, tungsten oxide and an oxide of an alkali or alkali-earth metal supported by a carrier.The method according to the present invention makes it possible to increase the yield of vinylaromatic compounds, obtain individual isomers of vinyltoluene or vinylxylene and efficiently utilize the part of the alkyl radical of the alkylaromatic compound lost in the prior art method.

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: 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: A process for producing unsaturated hydrocarbons which comprises contacting a paraffin, monoolefin and/or alkylaromatic compounds with a catalyst at a temperature within the range of from 400.degree. to 700.degree. C. in the presence of an inert gas and/or steam. The catalyst comprises a carrier having deposited thereonto an oxide of molybdenum in an amount of from 5 to 35% by weight of the catalyst. As the carrier, use is made of a granulated porous crystalline silica modified with magnesia in an amount of from 1 to 20% by weight of the carrier; a granulated magnesium-titanium carrier consisting of 50 to 95% by weight of MgO and 50 to 5% by weight of TiO.sub.2, or a granulated magnesium-aluminum carrier consisting of 70 to 95% by weight of MgO and 5 to 30% by weight of Al.sub.2 O.sub.3. Through the spent catalyst an oxygen-containing gas is passed at a temperature within the range of from 400.degree. to 700.degree. until catalytic activity is restored to the catalyst.

Abstract: Magnesium chromite dehydrogenation catalysts are improved by incorporation therein up to about 10% of an alkali metal.

Abstract: Vinyl cyclohexene is converted to styrene at 170.degree. C.-360.degree. C. in the presence of copper chromite catalyst.

Abstract: Addition of small amounts of oxidic compounds of aluminum, cadmium, magnesium, manganese, nickel, uranium, and the rare earths to iron-potassium-vanadium oxide catalysts useful in the dehydrogenation of hydrocarbons to the corresponding more unsaturated hydrocarbons results in an improved catalyst.