Abstract: Dehydrogenation catalyst compositions for alkylaromatics and dehydrogenation processes 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 catalyst modifier combination of calcium and bismuth compounds, e.g., calcium oxide and bismuth trioxide. Utilization of particular amounts of calcium and bismuth compounds 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 or the selective dehydrogenation of ethylbenzene to form styrene in improved yields.

Abstract: There is provided a process for producing aromatic hydrocarbons. The process involves contacting one or more non-aromatic compounds, such as propane, propylene, or methanol, with a catalyst containing a zeolite, such as ZSM-5. The zeolite is modified with phosphorus oxide by impregnating the zeolite with a source of phosphate ions, such as an aqueous solution of an ammonium phosphate, followed by calcination.

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: 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: There is provided a process for producing aromatic hydrocarbons. The process involves contacting one or more non-aromatic compounds, such as propane, propylene, or methanol, with a catalyst containing a zeolite, such as ZSM-5. The zeolite is modified with phosphorus oxide by impregnating the zeolite with a source of phosphate ions, such as an aqueous solution of an ammonium phosphate, followed by calcination.

Abstract: There is provided a process for producing aromatic hydrocarbons from paraffins. The process involves contacting one or more C.sub.2 -C.sub.12 alkanes with a catalyst containing a zeolite, such as ZSM-5, modified with one or more oxides of Group IIIA, IVA or VA elements, such as Sc, Ti or V. The presence of these particular oxide modifiers has been observed to result in greater yields of aromatics including BTX.

Abstract: There is provided a process for producing aromatic hydrocarbons enriched in benzene content. The process involves contacting one or more C.sub.2 -C.sub.8 non-aromatic hydrocarbons, such as propylene, with a catalyst containing a zeolite, such as ZSM-5. The proportion of benzene in the aromatics produced is increased by including hydrogen sulfide (i.e. H.sub.2 S) in the feedstock.

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: 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 method is provided for treating modified ZSM-5 type zeolite catalysts with water vapor in order to enhance the aromatics conversion activity and/or the para-selective properties of such catalysts for the conversion of aromatic materials. The modified zeolites so treated are those which contain a minor proportion of a difficultly reducible oxide such as magnesium oxide, calcium oxide and/or phosphorus oxide. Such catalyst compositions can be used in alkylation, transalkylation or disproportionation processes to provide improved yields of alkylated aromatic product mixtures having exceptionally high concentrations of the para-dialkylbenzene isomer.

Abstract: A modified zeolite catalyst composition is provided for the conversion of aromatic compounds to dialkylbenzene compounds rich in the 1,4-dialkylbenzene isomer. The reaction is carried out in the presence of a zeolite catalyst having a silica to alumina mole ratio of at least 12 and a constraint index of about 1-12, said catalyst having been modified prior to use by treatment with compounds of the Group VI A metals (Cr, Mo, W), and optionally phosphorus, followed by conversion of these elements to the oxide form, thereby incorporating these oxides into the crystal structure of the zeolite. This modification enhances the ability of the zeolite to selectively catalyze the production of the 1,4-dialkylbenzene isomer.

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: A process for alkylation of aromatic hydrocarbon reactants to dialkylbenzene products, whereby chemically modified zeolite catalysts are treated with an organic acid to enhance their intrinsic para-selectivity in the alkylation reaction. The modified zeolites which may be so reselectivated or improved comprise those crystalline zeolites having a constraint index of 1 to 12, a silica to alumina mole ratio of at least 12, and having a minor proportion of the oxide form of one or more chemical elements (e.g. phosphorus and magnesium) deposited thereon.

Abstract: A zeolite catalyst composition suitable for para-selective conversion of substituted aromatic compounds, e.g. conversion of aromatic compounds to dialkylbenzene compounds rich in the 1,4-dialkylbenzene isomer. Such a composition comprises a zeolite catalyst component having a silica to alumina mole ratio of at least 12 and a constraint index of about 1 to 12, and a minor amount, e.g., at least 0.25 weight percent of the elements iron and/or cobalt and optionally the element phosphorus, said elements being present in the form of their oxides.

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 process is provided for treating modified ZSM-5 type zeolite catalysts with carboxylic acid (or anhydride) and water vapor treating agents in order to enhance the para-selective properties of such catalysts for the alkylation of aromatic materials without significantly diminishing catalyst activity. The modified zeolites so treated are those which contain a minor proportion of a difficulty reducible oxide such as magnesium oxide, calcium oxide and/or phosphorus oxide. Such catalyst compositions can be used in alkylation processes to provide alkylated aromatic product mixtures having exceptionally high concentrations of the para-dialkylbenzene isomer.

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: 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.