Abstract: A multi-reactor hydrocarbon catalytic conversion system includes at least three reactors, a feed source for providing hydrocarbon feed to the reactors and apparatus for sequentially backwardly rotating the reactors during process mode operation of the reactors. In each of a series of sequential cycles, at least one reactor currently operates in a regeneration mode position, while other reactors operate in process mode positions. A reactor having freshest catalyst is in a last process mode position, and a reactor having relatively least fresh catalyst is in a first process mode position. The reactor having relatively least fresh catalyst receives fresh feed first from the feed source, and the reactor having freshest catalyst receives the partially converted feed last. Method and apparatus are provided for rotation of the reactors, without the necessity of stopping operation of the catalytic conversion process while the shifting of the reactors is being performed.

Abstract: A methanol-to-gasoline (MTG) catalytic conversion system in which the conversion is conducted in a fixed bed catalytic reactor. A C.sub.3 -C.sub.4 hydrocarbon diluent is generated from pressurized liquid effluent and recycled to the fixed bed reactor in order to dissipate the heat of reaction.

Abstract: A methanol-to-gasoline (MTG type) conversion process in which the conversion is conducted in a fixed bed catalytic reactor. A C.sub.3 -C.sub.4 hydrocarbon diluent is generated from the effluent in a series of steps and recycled to the fixed bed reactor in order to dissipate the heat of reaction.

Abstract: An improved continuous process for converting lower olefinic hydrocarbon feedstock to C.sub.5.sup.+ liquid hydrocarbons by contacting vapor phase olefinic feedstream with acid zeolite catalyst in the presence of recycled diluent stream rich in C.sub.3 -C.sub.4 hydrocarbons in an enclosed reactor at elevated temperature and pressure. The improved technique comprises a system for cooling reactor effluent to recover a heavier hydrocarbon stream containing a mixture of C.sub.3 -C.sub.4 hydrocarbons and C.sub.5.sup.+ hydrocarbons and debutanizing the heavier hydrocarbons below reactor pressure to obtain a C.sub.5.sup.+ product stream and a condensed C.sub.3 -C.sub.4 hydrocarbon stream. Operating efficiencies are realized in the heat exchange system by reboiling the debutanized C.sub.5.sup.+ hydrocarbon product stream with hot reactor effluent, and by recycling and combining at least a portion of the condensed C.sub.3 -C.sub.4 hydrocarbon stream to dilute liquid olefin hydrocarbon feedstock.

Abstract: A continuous catalytic process for oligomerizing lower olefins to heavier hydrocarbons wherein a continuous liquid olefinic feedstream is diluted with a liquid alkane stream, is improved by a technique which comprises cooling catalytically converted effluent, fractionating the effluent to obtain a condensed lower aliphatic recycle stream, a liquid C.sub.3 -C.sub.4 product stream, a liquid product stream consisting essentially of C.sub.5.sup.+ hydrocarbons and a gaseous C.sub.2.sup.- gaseous stream by the sequential fractionation steps of: debutanizing the cooled effluent to obtain the liquid C.sub.5.sup.+ hydrocarbon stream and a condensed lower aliphatic stream; de-ethanizing a portion of the lower aliphatic stream to recover gaseous offgas stream and a C.sub.3 -C.sub.4 alkane product stream; and optionally recycling at least a portion of the condensed aliphatic stream from the debutanizing step for dilution of the olefinic feedstream.