A method to recover refrigeration credit from propane feed to a propane dehydrogenation reactor by fully condensing a Depropanizer overhead stream, letting the condensed stream down in pressure, and vaporizing the stream at lower pressure against process streams to recover refrigeration credit.

A process and apparatus reboil a propylene splitter bottoms by heat exchange and/or a deethanizer bottoms stream with a compressed propylene splitter overhead stream. Use of single splitter compressor and operation of the propane-propylene splitter column at lower pressure are enabled, whereas conventionally two splitter compressors and higher splitter pressure were necessary to provide a propylene product stream and a propane recycle stream of equivalent quality.

A process and apparatus reboil a propylene splitter bottoms by heat exchange and/or a deethanizer bottoms stream with a compressed propylene splitter overhead stream. Use of single splitter compressor and operation of the propane-propylene splitter column at lower pressure are enabled, whereas conventionally two splitter compressors and higher splitter pressure were necessary to provide a propylene product stream and a propane recycle stream of equivalent quality.

A process for the purification of isobutene from a C4 stream with at least 1-butene, 2-butene, isobutane and isobutene includes isomerizing 1-butene from a stream of material which is concentrated in isobutane and isobutene obtained from the C4 stream into 2-butene, using a catalyst in an isomerization reactor; supplying a product stream from the isomerization reactor to a rectification column; and providing a stream of material which is concentrated in isobutene. A processing facility is utilized for the purification of isobutene from the C4 stream.

An on-board fuel separation system includes a supply fuel tank configured to store an input fuel stream; a fuel separator fluidly coupled to the supply fuel tank and configured to separate the input fuel stream into a first fractional fuel stream and a second fractional fuel stream. The fuel separator includes a membrane that includes a plurality of pores sized based on a molecular size of one or more components of the first fractional fuel stream. The system includes a first fractional fuel tank fluidly coupled to the fuel separator to receive the first fractional fuel stream passed through the membrane and defined by a first auto-ignition characteristic value. The system includes a second fractional fuel stream coupled to the fuel separator to receive the second fractional fuel stream from the fuel separator that is defined by a second auto-ignition characteristic value that is different than the first auto-ignition characteristic value.

A process for extracting isoprene from a pyrolysis gas mixture or a C5 fraction wherein isoprene is purified by plural extractive distillations in the presence of a polar solvent and cyclopentadiene is effectively removed and recycled as a feedstock without being converted into its dimer, dicyclopentadiene. The isoprene recovered from the process described is more than 99.5% pure.

A process for extracting isoprene from a pyrolysis gas mixture or a C5 fraction wherein isoprene is purified by plural extractive distillations in the presence of a polar solvent and cyclopentadiene is effectively removed and recycled as a feedstock without being converted into its dimer, dicyclopentadiene. The isoprene recovered from the process described is more than 99.5% pure.

Linear alpha olefins (LAOS) may be formed by oligomerization of ethylene in the presence of a Ziegler-type catalyst. The presence of trace water during oligomerization can result in unwanted formation of insoluble higher oligomers or polymer. Methods for limiting the presence of water during ethylene oligomerization reactions may include separating residual ethylene and 1-butene from an LAO product stream to form a higher LAO-enriched stream comprising C.sub.6+ LAOs, separating 1-hexene as an overhead stream from the higher-LAO enriched stream using a first distillation column, obtaining separated solvent as a side stream from the first distillation column or as a side stream from a first of one or more downstream distillation columns, and returning the separated solvent to a reactor in a recycled solvent stream. The recycled solvent stream passes through one or more driers before returning to the reactor.

Linear alpha olefins (LAOS) may be formed by oligomerization of ethylene in the presence of a Ziegler-type catalyst. The presence of trace water during oligomerization can result in unwanted formation of insoluble higher oligomers or polymer. Methods for limiting the presence of water during ethylene oligomerization reactions may include separating residual ethylene and 1-butene from an LAO product stream to form a higher LAO-enriched stream comprising C.sub.6+ LAOs, separating 1-hexene as an overhead stream from the higher-LAO enriched stream using a first distillation column, obtaining separated solvent as a side stream from the first distillation column or as a side stream from a first of one or more downstream distillation columns, and returning the separated solvent to a reactor in a recycled solvent stream. The recycled solvent stream passes through one or more driers before returning to the reactor.

Processes and apparatuses for producing a C.sub.8 aromatic isomer product are provided. The process comprises introducing a reformate stream comprising aromatic hydrocarbons to a reformate splitter column to provide a plurality of streams. One or more streams comprising at least one stream from the plurality of streams is passed to a reformate upgrading unit to obtain an upgraded reformate stream. The upgraded reformate stream is passed to an aromatics stripper column to provide an aromatics stripper sidedraw stream comprising C.sub.8 aromatic hydrocarbons. The aromatics stripper sidedraw stream is passed to a xylene separation unit to provide the C.sub.8 aromatic isomer product and a raffinate product stream. At least a portion of the raffinate product stream is processed in a liquid phase isomerization unit to obtain an isomerized stream.