Abstract: In a process for dehydrocyclization of C.sub.6 -C.sub.12 alkanes in the presence of steam and a bed of a catalyst containing a Group IIA or IIB metal aluminate and a Group VIII metal, an oxygen containing gas is injected into the catalyst bed. The results of the oxygen injection are the internal generation of heat, a lower required steam to hydrocarbon ratio, and increased yield of aromatics.

Abstract: A hydrogen donor solvent selected from the group consisting of a full range crude oil and an atmospheric topped crude oil is used in a hydrovisbreaking process. The heavy fraction being processed is heated in the presence of hydrogen and the solvent under suitable hydrovisbreaking conditions. As a result, the amount of heavies in the feed to the hydrovisbreaking process is substantially reduced.

Abstract: A continuous process for the alkylation of an alkylatable hydrocarbon with an alkylating agent in the presence of an acid-type catalyst, including; contacting an alkylatable hydrocarbon with an alkylating agent in the presence of an acid-type catalyst at a temperature and pressure and for a time sufficient to alkylate the alkylatable hydrocarbon; separating the reaction effluent stream into an alkylate product phase and a catalyst phase containing catalyst-soluble oil; cooling the catalyst phase to a temperature essentially equal to the alkylation reaction temperature; recycling the cooled catalyst phase to the alkylation reaction; contacting a diolefinic hydrocarbon with an acid-type catalyst at a temperature and pressure sufficient to form additional catalyst-soluble oil and combining the additional catalyst-soluble oil with the circulating catalyst phase.

Abstract: A stream comprising isobutylene and n-butenes is processed to effect dimerization of the isobutylene, and the resulting isobutylene dimer is fed to an alkylation step.

Abstract: A process for catalytic reforming of hydrocarbons which comprises contacting aliphatic hydrocarbons with steam and a dehydrocyclization catalyst under dehydrocyclization conditions to form a vapor stream containing aromatics and nonaromatics, separating at least a portion of the vapor stream which is compressed, heated, and recycled to the dehydrocyclization reaction to minimize steam diluent requirements for the process.

Abstract: A continuous process for the alkylation of an alkylatable hydrocarbon with an alkylating agent in the presence of an acid-type catalyst, including; contacting an alkylatable hydrocarbon with an alkylating agent in the presence of an acid-type catalyst at a temperature and pressure and for a time sufficient to alkylate the alkylatable hydrocarbon; separating the reaction effluent stream into an alkylate product phase and a catalyst phase containing catalyst-soluble oil; cooling the catalyst phase to a temperature essentially equal to the alkylation reaction temperature; recycling the cooled catalyst phase to the alkylation reaction; contacting a diolefinic hydrocabon with an acid-type catalyst at a temperature and pressure sufficient to form additional catalyst-soluble oil and combining the additional catalyst-soluble oil with the circulating catalyst phase.

Abstract: A method of alkylating an alkylatable hydrocarbon with different alkylating agents, at different reaction temperatures and in a single reaction zone, in which an alkylatable hydrocarbon is contacted with an acid-type catalyst and at different points in an elongated reaction zone, the reaction zone effluent is separated into a hydrocarbon phase and a catalyst recycle phase and the reaction temperatures of the various alkylating agents are maintained at different temperatures by splitting the recycle catalyst phase into an equal number of streams and adjusting the reaction temperatures by adjusting the temperatures of the recycle catalyst phase streams, the relative proportions of the recycle catalyst phase streams or both. A method of starting-up the process and apparatus for conducting the process are also disclosed.

Abstract: In a conventional reactor into which at one end portion there are fed olefin, isoparaffin and HF acid, or other catalysts, and from which an alkylate containing product is passed to a phase separator or settling zone, there is added to the reactor to a downstream portion therein, beyond the original point of entry of the first olefin feed a second portion of olefin feed together with hydrocarbon phase recycled from the phase separator or settling zone.

Abstract: A mixture of C.sub.4 -hydrocarbons is extractively distilled with sulfolane and acetone or methylethyl ketone as the selective solvent; the rich solvent containing 1,3-butadiene and vinylacetylene is stripped and a small quantity of the ketone is allowed to leave overhead. Thereby the further fractionation of the stripper overhead results in a very efficient separation of 1,3-butadiene and vinylacetylene.

Abstract: A C.sub.4 -hydrocarbon feedstream containing butenes, butadiene, and vinylacetylene is subjected to a first extractive distillation with a selective solvent to remove butenes and a first portion of vinylacetylene as the extract; by the extraction with a minor quantity of methylethyl ketone in the selective solvent in this step, it has been found that a major portion of the vinylacetylene can be rejected, together with the butenes in the rich extract and that simultaneously the quantity of butadiene extracted could be considerably reduced; in a second extractive distillation the butadiene-rich raffinate of the first extractive distillation is further purified by extractive distillation using a mixture of sulfolane and methylethyl ketone as the solvent; after solvent stripping, the butadiene stream is finally purified in a fractionation step, wherein further vinylacetylene is removed.

Abstract: A mixture of methylethylsulfone and at least one compound from the group including methylethylketone, acetone, and tetrahydrofuran is employed as a selective solvent in extractive distillation process for separation of diolefins from olefins.

Abstract: Butadiene is produced in relatively pure form by an oxidative dehydrogenation process in which a crude butadiene stream comprising butadiene, butylenes, vinyl acetylene and propylene is first extractively distilled with an extractant consisting of a sulfolane/acetone mixture. From a purified stream consisting essentially of butadiene and vinyl acetylene, the vinyl acetylene in a second extractive distillation step is removed using a sulfolane/acetone mixture as the extractant to produce a pure butadiene stream.

Abstract: A stream containing styrene and mixed xylenes, such as may be recovered from pyrolysis gasoline, is fractionated to obtain a stream containing ortho-xylene and styrene. Styrene is separated from the latter stream by an extraction process which employs succinonitrile as the solvent. Styrene is selectively absorbed by the succinonitrile, and is subsequently recovered from the resulting extract phase.

Abstract: Hydrocarbons having different degrees of saturation are separated by extractive distillation using selective solvent comprising a mixture of dimethylsulfone, methylethylketone and sulfolane.

Abstract: A mixture of n-butane and acetone is effectively separated by liquid-liquid extraction or extractive distillation using a sulfolane as the extractive solvent.