Abstract: The invention comprises an absorption heat pump to supply energy to a distillation process or an outside process. The streams used to effect the absorption heat pump are to be combined in any case as a feedstream to a conversion process, and energy thus is conserved by avoiding the necessity of reseparating the streams.

Abstract: The present process comprises a means for energy savings in a process pump by combining the pump with a power-recovery turbine. The invention is particularly useful in the separation of a desired product from a mixture of components using simulated-moving-bed adsorption associated with a large circulating stream with a power-recovery turbine feature for conservation of energy relative to the known art. The improvement is particularly applicable to a process for the separation of para-xylene from mixed C8 aromatics.

Abstract: Disclosed is a mixer-distributor-collector apparatus for use between beds of solid particles in a fluid-solid contacting vessel. The apparatus includes a solids retaining screen, fluid deflector, passageway, fluid distributor, and flow manipulator. The flow manipulator is a device such as a honeycomb, porous solid, perforated plate, screen, or grid having an open area greater than the open area of the fluid distributor and is located below and spaced apart from the fluid distributor. The apparatus improves the fluid flow characteristics by minimizing or eliminating fluid velocity jets and/or other turbulence which can disturb the downstream particle bed. In an exemplary application, the invention finds use in simulated moving bed (SMB) adsorptive separation processes.

Abstract: Meta-xylene is recovered from admixture with other C8 aromatic hydrocarbons including ortho-xylene by liquid phase adsorptive separation. Performance is improved by reducing the concentration of ortho-xylene through adding a sidecut to a prefractionator preparing the feedstock to adsorptive separation.

Abstract: The process includes at least two adsorptive separation zones to separate para-xylene from a feed stream comprising C8 aromatic hydrocarbons and at least one C9 aromatic hydrocarbon component. An adsorbent comprising X or Y zeolite and a heavy desorbent are used in the first adsorptive separation zone to produce an extract stream comprising para-xylene and a raffinate stream comprising para-xylene depleted C8 aromatic hydrocarbons, the C9 aromatic hydrocarbon, and the desorbent. The raffinate stream is separated in a raffinate distillation zone to produce a stream comprising the first desorbent component and the C9 aromatic hydrocarbon which stream is further separated in a second adsorptive distillation zone to produce a stream comprising the desorbent and a C9 aromatic hydrocarbon stream.

Abstract: The invention is an adsorptive separation process for producing a para-xylene product from a feed stream comprising para-xylene, at least one other C8 aromatic, and a C9 aromatic. An adsorbent comprising X or Y zeolite and a desorbent comprising para-diethylbenzene (p-DEB) are used in an adsorptive separation zone to produce an extract stream comprising para-xylene, p-DEB, and the C9 aromatic and a raffinate stream comprising the at least one other C8 aromatic, the C9 aromatic, and p-DEB. The extract stream is separated in an extract distillation zone to produce a second desorbent stream comprising the C9 aromatic and p-DEB and the raffinate stream is separated in a raffinate distillation zone to produce a third desorbent stream comprising the C9 aromatic and p-DEB. At least a portion of at least one of the second desorbent stream and the third desorbent stream is further separated in a desorbent distillation zone to produce a stream comprising the C9 aromatic.

Abstract: Adsorbents and methods for the adsorptive separation of meta-xylene from a mixture containing at least one other C8 aromatic hydrocarbon (e.g., a mixture of ortho-xylene, meta-xylene, para-xylene, and ethylbenzene) are described. Suitable adsorbents comprise sodium zeolite Y having an average crystallite size from about 50 to about 700 nanometers. The adsorbents provide improved separation efficiency, which may be associated with a higher meta-xylene mass transfer rate and/or other beneficial effects. Exemplary desorbents for use in the process may comprise toluene, benzene, or indan.

Abstract: The apparatus includes at least two adsorptive separation zones to separate para-xylene from a feed stream comprising C8 aromatic hydrocarbons and at least one C9 aromatic hydrocarbon component. The first adsorptive separation zone delivers a raffinate stream to a raffinate distillation zone and an extract stream to an extract distillation zone. The raffinate distillation zone delivers a stream to the second adsorptive separation zone and at least one of the extract distillation zone and raffinate distillation zone delivers a recycle stream to the first adsorptive separation zone.

Abstract: The process includes at least two adsorptive separation zones to separate para-xylene from a feed stream comprising C8 aromatic hydrocarbons and at least one C9 aromatic hydrocarbon component. An adsorbent comprising X or Y zeolite and a heavy desorbent are used in the first adsorptive separation zone to produce an extract stream comprising para-xylene and a raffinate stream comprising para-xylene depleted C8 aromatic hydrocarbons, the C9 aromatic hydrocarbon, and the desorbent. The raffinate stream is separated in a raffinate distillation zone to produce a stream comprising the first desorbent component and the C9 aromatic hydrocarbon which stream is further separated in a second adsorptive distillation zone to produce a stream comprising the desorbent and a C9 aromatic hydrocarbon stream.

Abstract: Adsorbents and methods for the adsorptive separation of meta-xylene from a mixture containing at least one other C8 aromatic hydrocarbon (e.g., a mixture of ortho-xylene, meta-xylene, para-xylene, and ethylbenzene) are described. Suitable adsorbents comprise sodium zeolite Y having an average crystallite size from about 50 to about 700 nanometers. The adsorbents provide improved separation efficiency, which may be associated with a higher meta-xylene mass transfer rate and/or other beneficial effects. Exemplary desorbents for use in the process may comprise toluene, benzene, or indan.

Abstract: The subject process obtains a high yield of high-purity para-xylene from 2,4,4-trimethylpentene as contained in butene dimer. A process combination may include dimerization of the isobutene to obtain C8 iso-olefins and isoparaffins, aromatization of the dimerized C8 product, and recovery of high-purity para-xylene from the dimerized product by low-intensity crystallization. Aromatization is effected using a catalyst comprising a large-pore molecular sieve. Each of the processing steps may be tailored to the overall objective of high para-xylene yield from a relatively inexpensive feedstock.

Abstract: The subject process obtains a high yield of high-purity para-xylene from a butene dimer feed. The process may include dimerization of isobutene to obtain a butene dimer comprising C8 iso-olefins and isoparaffins, aromatization of the dimerized C8 product, and recovery of high-purity para-xylene from the dimerized product by low-intensity crystallization. Aromatization is effected using a non-acidic, non-zeolitic catalyst. Each of the processing steps may be tailored to the overall objective of high para-xylene yield from a relatively inexpensive feedstock.

Abstract: Low-value mixed butanes are processed to obtain a high yield of high-purity para-xylene. Processing steps may comprise fractionation to recover isobutane, dehydrogenation of the isobutane to isobutene, dimerization of the isobutene to obtain C8 iso-olefins and isoparaffins, aromatization of the dimerized C8 product, and recovery of high-purity para-xylene from the dimerized product by low-intensity crystallization. The availability of isobutane may be increased by isomerization of normal butane. Each of the processing steps may be tailored to the overall objective of high para-xylene yield from a relatively inexpensive feedstock.

Abstract: A multi-zone process for the conversion of a hydrocarbon feedstock comprising cyclic compounds to produce aromatic compounds, and in particular xylene compounds. A naphtha boiling range stream having a boiling point range from about 71° C. (160° F.) to about 216° C. (420° F.) is reformed and/or transalkylated within reforming and transalkylation zones to produce an aromatics-rich high-octane stream containing xylene with increased xylene purity.

Abstract: A process for the production of low sulfur diesel and aromatic compounds wherein C9+ hydrocarbons are hydrocracked to produce low sulfur diesel and a naphtha boiling range stream which is transalkylated in an integrated transalkylation zone to produce xylene.

Abstract: Disclosed is a mixer-distributor-collector apparatus for use between beds of solid particles in a fluid-solid contacting vessel. The apparatus includes a solids retaining screen, fluid deflector, passageway, fluid distributor, and flow manipulator. The flow manipulator is a device such as a honeycomb, porous solid, perforated plate, screen, or grid having an open area greater than the open area of the fluid distributor and is located below and spaced apart from the fluid distributor. The apparatus improves the fluid flow characteristics by minimizing or eliminating fluid velocity jets and/or other turbulence which can disturb the downstream particle bed. In an exemplary application, the invention finds use in simulated moving bed (SMB) adsorptive separation processes.

Abstract: An aromatics complex flow scheme has been developed. The isomerized xylenes effluent from a xylene recovery zone is recycled to a transalkylation stripper without requiring C8 aromatic hydrocarbons to be separated. This improvement results in an aromatics complex with savings on capital and utility costs and an improvement on the return on investment in such a complex.

Abstract: An aromatics complex flow scheme has been developed in which C7-C8 aliphatic hydrocarbons are recycled to an isomerization unit of a xylene recovery zone to increase the efficiency of the isomerization unit. This improvement results in an aromatics complex with savings on capital and utility costs and an improvement on the return on investment.

Abstract: A multi-zone process for the production of low sulfur diesel and aromatic compounds wherein C9+ hydrocarbons are hydrocracked to produce low sulfur diesel and a naphtha boiling range stream which is reformed and transalkylated within reforming and transalkylation zones to produce an aromatics-rich high-octane stream containing xylene and to balance hydrogen needs.

Abstract: An aromatics complex flow scheme has been developed. C7-C8 aliphatic hydrocarbons are recycled to an isomerization unit of a xylene recovery zone to increase the efficiency of the isomerization unit. This improvement results in an aromatics complex with savings on capital and utility costs and an improvement on the return on investment.