A composite adsorbent for separating ethylbenzene from C8 arene by an adsorption distillation contains 1-50 mass % of a xylene adsorbent and 50-99 mass % of a carrier liquid. The carrier liquid is selected from one or two of alkane, aryl-substituted alkane, decalin and alkyl-substituted decalin. The alkane is C10-C26 alkane, and the aryl-substituted alkane is C13-C16 aryl-substituted alkane. The composite adsorbent can increase the volatility of ethylbenzene relative to other C8 arenes and thus can separate a high-purity ethylbenzene from C8 arene by the adsorption distillation.

A method for separating CO.sub.2 from C.sub.2 to C.sub.5 alkanes includes introducing a first stream including C.sub.2 to C.sub.5 alkanes and CO.sub.2 into a first separation zone, the first separation zone including a hydrocarbon solvent, and separating the first stream into a recycle stream and a second stream in the first separation zone. The recycle stream including CO.sub.2 and one or more of CO, H.sub.2, and CH.sub.4, and the second stream including C.sub.2 to C.sub.5 alkanes. The method further includes introducing the second stream into a second separation zone, and separating the second stream into a third stream and a fourth stream, wherein the third stream includes C.sub.2 alkanes and the fourth stream includes C.sub.3 to C.sub.5 alkanes.

A method for separating CO.sub.2 from C.sub.2 to C.sub.5 alkanes includes introducing a first stream including C.sub.2 to C.sub.5 alkanes and CO.sub.2 into a first separation zone, the first separation zone including a hydrocarbon solvent, and separating the first stream into a recycle stream and a second stream in the first separation zone. The recycle stream including CO.sub.2 and one or more of CO, H.sub.2, and CH.sub.4, and the second stream including C.sub.2 to C.sub.5 alkanes. The method further includes introducing the second stream into a second separation zone, and separating the second stream into a third stream and a fourth stream, wherein the third stream includes C.sub.2 alkanes and the fourth stream includes C.sub.3 to C.sub.5 alkanes.

A method for separating CO.sub.2 from C.sub.2 to C.sub.5 alkanes includes introducing a first stream including C.sub.2 to C.sub.5 alkanes and CO.sub.2 into a first separation zone, the first separation zone including a hydrocarbon solvent, and separating the first stream into a recycle stream and a second stream in the first separation zone. The recycle stream including CO.sub.2 and one or more of CO, H.sub.2, and CH.sub.4, and the second stream including C.sub.2 to C.sub.5 alkanes. The method further includes introducing the second stream into a second separation zone, and separating the second stream into a third stream and a fourth stream, wherein the third stream includes C.sub.2 alkanes and the fourth stream includes C.sub.3 to C.sub.5 alkanes.

A method for separating CO.sub.2 from C.sub.2 to C.sub.5 alkanes includes introducing a first stream including C.sub.2 to C.sub.5 alkanes and CO.sub.2 into a first separation zone, the first separation zone including a hydrocarbon solvent, and separating the first stream into a recycle stream and a second stream in the first separation zone. The recycle stream including CO.sub.2 and one or more of CO, H.sub.2, and CH.sub.4, and the second stream including C.sub.2 to C.sub.5 alkanes. The method further includes introducing the second stream into a second separation zone, and separating the second stream into a third stream and a fourth stream, wherein the third stream includes C.sub.2 alkanes and the fourth stream includes C.sub.3 to C.sub.5 alkanes.

A method of separating a feed stream in a distillation tower. Vapor is permitted to rise upwardly from a distillation section of the distillation tower. A feed stream is introduced into a controlled freeze zone section of the distillation tower, the controlled freeze zone section being situated above the distillation section. The feed stream is released above a level of a liquid retained by a melt tray assembly in the controlled freeze zone section. Vapor from the distillation section is directed into the liquid retained by the melt tray assembly. A solid is formed from the feed stream in the controlled freeze zone section.

A method of separating a feed stream in a distillation tower. Vapor is permitted to rise upwardly from a distillation section of the distillation tower. A feed stream is introduced into a controlled freeze zone section of the distillation tower, the controlled freeze zone section being situated above the distillation section. The feed stream is released above a level of a liquid retained by a melt tray assembly in the controlled freeze zone section. Vapor from the distillation section is directed into the liquid retained by the melt tray assembly. A solid is formed from the feed stream in the controlled freeze zone section.

An isomerization method consists of a deisobutanizer column receives feed comprising n-butane. The deisobutanizer column delivers its bottoms a portion to a reboiler and another portion along with hydrogen is routed to a isomerization reactor and the reactor effluent is returned to the column. A stabilizer which is integrated with the column, an overhead stream used as a reflux and bottoms containing an iso-butane-rich stream that is the iso-butane product stream. The column overhead effluent is routed to separator, which splits the hydrocarbons and effluent, where the hydrocarbons are routed to deisobutanizer column and effluent recycled to stabilizer, where the stabilizer separates the reactor effluent into product streams contains an iso-butane product stream, a n-butane product stream, and a lighter hydrocarbon product stream.

An isomerization method consists of a deisobutanizer column receives feed comprising n-butane. The deisobutanizer column delivers its bottoms a portion to a reboiler and another portion along with hydrogen is routed to a isomerization reactor and the reactor effluent is returned to the column. A stabilizer which is integrated with the column, an overhead stream used as a reflux and bottoms containing an iso-butane-rich stream that is the iso-butane product stream. The column overhead effluent is routed to separator, which splits the hydrocarbons and effluent, where the hydrocarbons are routed to deisobutanizer column and effluent recycled to stabilizer, where the stabilizer separates the reactor effluent into product streams contains an iso-butane product stream, a n-butane product stream, and a lighter hydrocarbon product stream.

An isomerization method consists of a deisobutanizer column receives feed comprising n-butane. The deisobutanizer column delivers its bottoms a portion to a reboiler and another portion along with hydrogen is routed to a isomerization reactor and the reactor effluent is returned to the column. A stabilizer which is integrated with the column, an overhead stream used as a reflux and bottoms containing an iso-butane-rich stream that is the iso-butane product stream.

The column overhead effluent is routed to separator, which splits the hydrocarbons and effluent, where the hydrocarbons are routed to deisobutanizer column and effluent recycled to stabilizer, where the stabilizer separates the reactor effluent into product streams contains an iso-butane product stream, a n-butane product stream, and a lighter hydrocarbon product stream.