Abstract: Gas separation processes are provided for separating dehydrogenation reaction products from a raw gas stream to recover hydrocarbons, specifically olefins, such as propylene and iso-butene, as well as unreacted feedstock. The processes employ a sequence of partial condensation steps, interspersed with membrane separation steps to raise the hydrocarbon dewpoint of the uncondensed gas, thereby avoiding the use of low-temperature or cryogenic conditions.

Abstract: Gas separation processes are provided for separating dehydrogenation reaction products from a raw gas stream to recover hydrocarbons, specifically olefins, such as propylene and iso-butene, as well as unreacted feedstock. The processes employ a sequence of partial condensation steps, interspersed with membrane separation steps to raise the hydrocarbon dewpoint of the uncondensed gas, thereby avoiding the use of low-temperature or cryogenic conditions.

Abstract: Gas separation processes are provided for separating dehydrogenation reaction products from a raw gas stream to recover hydrocarbons, specifically olefins, such as propylene and iso-butene, as well as unreacted feedstock. The processes employ a sequence of partial condensation steps, interspersed with membrane separation steps to raise the hydrocarbon dewpoint of the uncondensed gas, thereby avoiding the use of low-temperature or cryogenic conditions.

Abstract: A process for recovering unreacted olefin in a polyolefin manufacturing process comprising the treatment of a purge bin vent gas. The process involves cooling and condensing the vent gas (purge stream), which contains at least an olefin, a paraffin, and nitrogen, to produce a liquid condensate and an uncondensed (residual) gas stream. Both streams are then passed through membrane separation steps. The membrane separation of the uncondensed gas stream results in a residue stream containing mostly nitrogen and/or paraffin and a permeate stream enriched in either C2+ hydrocarbons or olefin, depending on the type of separation. The permeate from this step is recirculated within the process prior to the condensation step. The membrane separation of the condensate results in a residue stream containing paraffin and a permeate stream enriched in olefin, which may be recycled to the polymerization reactor.

Abstract: Gas separation processes are provided for separating dehydrogenation reaction products from a raw gas stream to recover hydrocarbons, specifically olefins, such as propylene and iso-butene, as well as unreacted feedstock. The processes employ a sequence of partial condensation steps, interspersed with membrane separation steps to raise the hydrocarbon dewpoint of the uncondensed gas, thereby avoiding the use of low-temperature or cryogenic conditions.

Abstract: Disclosed herein is a methanol production process that includes at least two membrane separation steps. Using the process of the invention, the efficiency of methanol production from syngas is increased by reducing the compression requirements of the process and/or improving the methanol product yield. As an additional advantage, the first membrane separation step generates a hydrogen-rich stream which can be sent for other uses. An additional benefit is that the process of the invention may debottleneck existing methanol plants if more syngas or carbon dioxide is available, allowing for feed of imported carbon dioxide into the synthesis loop. This is a way of sequestering carbon dioxide.

Abstract: Disclosed herein is a methanol production process that includes at least two membrane separation steps. Using the process of the invention, the efficiency of methanol production from syngas is increased by reducing the compression requirements of the process and/or improving the methanol product yield. As an additional advantage, the first membrane separation step generates a hydrogen-rich stream which can be sent for other uses. An additional benefit is that the process of the invention may debottleneck existing methanol plants if more syngas or carbon dioxide is available, allowing for feed of imported carbon dioxide into the synthesis loop. This is a way of sequestering carbon dioxide.