Abstract: A process for producing para-xylene and ethylbenzene from C8 aromatics containing ethylbenzene includes the steps of sending C8 aromatics containing ethylbenzene to an ethylbenzene liquid-phase adsorption separation device, wherein a suction liquid containing ethylbenzene and a suction residual liquid are obtained after the adsorption separation, and the desorbents in the suction liquid and the suction residual liquid are removed to obtain ethylbenzene and a suction residual oil; sending the suction residual oil to a para-xylene adsorption separation device, and unadsorbed components are discharged as a raffinate from the adsorbent bed; the adsorbent bed is rinsed with a desorbent to desorb the para-xylene therein and obtain an extract; the desorbents in the extract and the raffinate are respectively removed to obtain para-xylene and a raffinate oil; sending the raffinate oil to a xylene isomerization device to carry out xylene isomerization, and the isomerization product is fractionated.

Abstract: Apparatus and process for converting aromatic compounds, comprising/using: a fractionating train (4-7) suitable for extracting at least one benzene-comprising fraction (22), one toluene-comprising fraction (23) and one fraction (24) comprising xylenes and ethylbenzene from the feedstock (2); a xylene separating unit (10) suitable for treating the fraction comprising xylenes and ethylbenzene and producing a para-xylene-comprising extract (39) and a raffinate (40) comprising ortho-xylene, meta-xylene and ethylbenzene; an isomerizing unit (11) for treating the raffinate and producing a para-xylene-enriched isomerizate (42), which is sent to the fractionated train; and an alkylating reaction section (13) for treating at least part of the benzene-comprising fraction with an ethanol source (30) and producing an alkylation effluent (31) comprising ethylbenzene, which is sent to the isomerizing unit.

Abstract: Processes and apparatus for analyzing fluid properties of a stream are described. The processes utilize a simulated moving bed system and a rotary valve. The processes involve sending a portion of the pump-around stream to a side chamber where the moisture content of the adsorbent in the side chamber or one or more fluid properties of the stream or both are measured using an analyzer specific to each fluid property.

Abstract: Provided is a hybrid process for producing high-purity para-xylene from a feedstock of aromatic hydrocarbon isomer fractions having 8 carbon atoms, in a liquid phase. The process includes a liquid chromatography separation step and a crystallization step of the para-xylene from the purified stream of para-xylene obtained at the separation step.

Abstract: The present invention relates to zeolite adsorbents based on agglomerated zeolite X crystals comprising barium, potassium and sodium. These adsorbents find applications in the separation of aromatic C8 isomer fractions and especially xylene.

Abstract: Para-xylene is separated from a mixture of C8 aromatics using a simulated moving bed (SMB) adsorption process, wherein a MOF is used as an adsorbent and an alkane or alkene having 7 or less carbon atoms, such as hexane or heptane is used as desorbent. Because of the difference in boiling points of a hexane or heptane desorbent as compared to conventional desorbents such as toluene or para-diethylbenzene, less energy is required to separate hexane or heptane from C8 aromatics by distillation than the energy required to separate toluene or diethylbenzene from C8 aromatics by distillation.

Abstract: Disclosed is a process for recovering paraxylene in which a first simulated moving bed adsorption unit is used to produce two extract streams—one rich in paraxylene and a paraxylene-rich extract stream that is lean in ethylbenzene and an ethylbenzene-rich extract stream that is lean in paraxylene- and a paraxylene-depleted raffinate stream. A significant amount of the ethylbenzene is removed in the ethylbenzene-rich extract stream (at least enough to limit buildup in the isomerization loop), so the paraxylene-depleted raffinate stream may be isomerized in the liquid phase. Avoiding vapor phase isomerization saves energy and capital, as liquid phase isomerization requires less energy and capital than the vapor phase isomerization process due to the requirement of vaporizing the paraxylene-depleted stream and the use of hydrogen, which requires an energy and capital intensive hydrogen recycle loop.

Abstract: Processes for the energy efficient recycle of naphthenes in a paraxylene manufacturing process comprise partially condensing a reactor effluent and using a sidedraw tower apparatus. The naphthenes are efficiently separated into the sidedraw stream of the sidedraw tower apparatus. At least a portion of the sidedraw stream is directed to a paraxylene recovery section that produces a paraxylene product and a paraxylene lean stream comprising essentially all of the naphthenes in the sidedraw stream directed to the paraxylene recovery section. The paraxylene lean stream is recycled back to the reactor thereby preventing excessive loss of naphthenes from the processes.

Abstract: The present invention describes a process for the separation of xylenes in simulated counter-current utilising at least one adsorber with a limited cumulated total height (Hcu) of adsorbent and a superficial velocity (Vsl) of less than 2 cm/s.

Abstract: This invention describes a process for separation of xylenes for the purpose of the production of high-purity metaxylene, a simulated countercurrent process using at least one adsorber with a limited cumulative total level (Hcu) of adsorbent at a surface velocity (Vsl) that is less than 2 cm/s.

Abstract: The present invention relates to aggregate zeolitic adsorbents based on zeolite X and zeolite LSX. These adsorbents are particularly suitable for separating C8 aromatic isomers and in particular xylenes, separating sugars, separating polyhydric alcohols, separating isomers of substituted toluenes, separating cresols, separating dichlorobenzenes.

Abstract: A process according to various approaches includes flushing an intermediate transfer line between a raffinate stream transfer line and a desorbent stream transfer line away from the adsorptive separation chamber to remove residual fluid including desorbent from intermediate transfer line. The process may include directing the residual fluid flushed from the intermediate transfer line to a recycle stream to introduce the residual fluid into the adsorptive separation chamber.

Abstract: A process according to various approaches includes flushing an intermediate transfer line between a raffinate stream transfer line and a desorbent stream transfer line away from the adsorptive separation chamber to remove residual fluid including desorbent from intermediate transfer line. The process may include directing the residual fluid flushed from the intermediate transfer line to a recycle stream to introduce the residual fluid into the adsorptive separation chamber.

Abstract: Embodiments of adsorbents for separating para-xylene from a mixture of C8 alkyl aromatic hydrocarbons, methods for making such adsorbents, and methods for separating para-xylene using such adsorbents are provided. In one example, an adsorbent comprises a binderless adsorbent. The binderless adsorbent comprises zeolite X and has a K2O/(K2O+BaO+Na2O) molar ratio of from about 0.15 to about 0.4.

Abstract: An aromatics complex producing one or more xylene isomers offers a large number of opportunities to conserve energy by heat exchange within the complex. One previously unrecognized opportunity is through providing two parallel distillation columns operating at different pressures to separate C8 aromatics from C9+ aromatics. The parallel columns offer additional opportunities to conserve energy within the complex through heat exchange in associated xylene recovery facilities.

Abstract: Methods and systems for separating para-xylene are disclosed. In one exemplary embodiment, a method for separating para-xylene includes the steps of providing a feed stream including para-xylene and other C8 aromatic hydrocarbons to a first adsorbent bed within a radial flow simulated moving bed chamber and providing a desorbent stream to a second bed within the radial flow simulated moving bed chamber. The method further includes circulating the feed stream and the desorbent stream radially within the radial flow simulated moving bed chamber to third and fourth beds within the radial flow simulated moving bed chamber. Still further, the method includes withdrawing an extract stream including the para-xylene from the third bed and withdrawing a raffinate stream including the other C8 aromatic hydrocarbons from the fourth bed.

Abstract: A process for separating para-xylene from a plurality of aromatic compounds, wherein the process introduces a first mixed xylene stream comprising a plurality of xylene isomers into a first adsorptive separation unit to produce a first para-xylene enriched stream and a first raffinate stream. The process further introduces a second mixed xylene stream comprising a plurality of xylene isomers into a second adsorptive separation unit to produce a second para-xylene enriched stream and a second raffinate stream. The process further feeds both the first raffinate stream and the second raffinate stream into a shared raffinate column.

Abstract: A process according to various approaches includes flushing an intermediate transfer line between a raffinate stream transfer line and a desorbent stream transfer line away from the adsorptive separation chamber to remove residual fluid including desorbent from intermediate transfer line. The process may include directing the residual fluid flushed from the intermediate transfer line to a recycle stream to introduce the residual fluid into the adsorptive separation chamber.

Abstract: Purge fluid from a vessel head in an adsorption process is distributed to recovery processes according to the purity of product contained in the fluid. Extract-rich fluid thus is routed directly to recovery of the extract product. Distribution preferably is determined by internal positioning of feed, desorbent and product streams in the adsorption vessel.

Abstract: A process of producing PX comprising providing a C8+ feedstock, the C8+ feedstock has C8 hydrocarbons and C9+ hydrocarbons, to a crystallization unit under crystallization conditions to produce a PX enriched stream having a PX concentration of at least 99.5 wt % based on the weight of the PX enriched stream, wherein the C8+ feedstock has a PX concentration of at least 70 wt % based on total weight of xylenes in the C8+ feedstock, which the C8+ feedstock having a C9+ hydrocarbons concentration in a range from 1 wppm to 10 wt % based on the total weight of the C8+ feedstock.

Abstract: Binderless BaKX zeolitic adsorbents, methods for their production, and processes for their use in a liquid phase adsorptive separation process are provided. An adsorbent includes a binder-converted zeolite portion formed from x wt % kaolin clay binder and (100?x) wt % unconverted Zeolite X with a silica:alumina molar ratio of about 2.5. The kaolin clay binder is in the range of about 10 to about 20 wt %. Ba and K occupy cationic exchangeable sites within the adsorbent. K is in the range of about 0.25 to about 0.9% by weight and Ba is greater than about 31.6% by weight of the binderless BaKX zeolitic adsorbent. Cornstarch may be added to the Zeolite X and kaolin clay binder to increase adsorbent macro-porosity and pore volume. Productivity of the adsorbent is improved decreasing process operating costs. The mechanical strength of the adsorbent is also improved.

Abstract: A process according to various approaches includes flushing an intermediate transfer line between a raffinate stream transfer line and a desorbent stream transfer line away from the adsorptive separation chamber to remove residual fluid including desorbent from intermediate transfer line. The process may include directing the residual fluid flushed from the intermediate transfer line to a recycle stream to introduce the residual fluid into the adsorptive separation chamber.

Abstract: Purge fluid from a vessel head in an adsorption process is distributed to recovery processes according to the purity of product contained in the fluid. Extract-rich fluid thus is routed directly to recovery of the extract product. Distribution preferably is determined by internal positioning of feed, desorbent and product streams in the adsorption vessel.

Abstract: A device (SMB) for separation by simulated moving bed adsorption comprises a plurality of elementary zones Zi in series operating in a closed loop, each of said zones comprising, between two successive fluid injection or extraction points, a unique bed Li of adsorbant solid with volume VAi and a non-selective free volume Vi, in which the majority of the zones are ordinary elementary zones each having an identical volume VA of the same adsorbant S, and a substantially identical non-selective free volume equal to V; the device also comprises at least one particular elementary zone Z0, termed the particular elementary zone, comprising a non-selective free volume V0 which is greater than V, and a unique bed L0 of adsorbant S0 with volume VA0 which is less than VA, S0 having a volume adsorption capacity C0 which is greater than that, C, of S, such that the overall adsorption capacity C0×VA0 of Z0 is closer to the overall adsorption capacity C×VA of each of the ordinary elementary zones than the overall adsorption

Abstract: A process for separating para-xylene from a plurality of xylene isomers, wherein the process introduces at a first feed point a first mixed xylene stream comprising a plurality of xylene isomers into a first adsorptive separation unit to produce a first para-xylene enriched stream and a first raffinate stream, and introduces a second mixed xylene stream comprising a plurality of xylene isomers into a second adsorptive separation unit to produce a second raffinate stream. The process feeds both the first raffinate stream and the second raffinate stream into a raffinate column. The process further introduces an extract stream from the second adsorptive separation unit into a first input of a split extract column comprising an internal partition defining a first distillation zone and a second distillation zone.

Abstract: A process for separating a product from a multicomponent feedstream to an adsorption apparatus or system is described. The apparatus or system may comprise a moving-bed or a simulated moving-bed adsorption means. The product comprises at least one organic compound, such as an aryl compound with alkyl substitutes. In embodiments the conduits used to supply the feedstream to the apparatus or system are flushed with media of multiple grades. The improvement is a more efficient use of the desorbent. In embodiments the process achieves improvements in one or more of efficiency of adsorption separation, capacity of adsorption apparatus systems, and purity of product attainable by adsorption process.

Abstract: This invention relates to a method wherein a high-purity paraxylene can be produced efficiently by using a catalyst having a molecular sieving action (or shape selectivity) and being excellent in the catalytic activity without isomerization and adsorption-separation steps. More particularly, it relates to a method of producing a high-purity paraxylene, characterized in that MFI type zeolite having a primary particle size of not more than 100 ?m, a structure defining agent and silica material having an average particle size of not less than 10 nm but less than 1.0 ?m are used as a starting material, and a synthetic zeolite catalyst produced by subjecting the MFI type zeolite to a coating treatment with an aqueous solution obtained by mixing so as to satisfy X×Y<0.05 (wherein X is a concentration of the silica material (mol %) and Y is a concentration of the structure defining agent (mol %)) is used in the alkylation or disproportionation of at least one of benzene and toluene as a starting material.

Abstract: An aromatics complex producing one or more xylene isomers offers a large number of opportunities to conserve energy by heat exchange within the complex. One previously unrecognized opportunity is through providing two parallel distillation columns operating at different pressures to separate C8 aromatics from C9+ aromatics. The parallel columns offer additional opportunities to conserve energy within the complex through heat exchange in associated xylene recovery facilities.

Abstract: This invention describes a process for separation of xylenes for the purpose of the production of high-purity metaxylene, a simulated countercurrent process using at least one adsorber with a limited cumulative total level (Hcu) of adsorbent at a surface velocity (Vsl) that is less than 2 cm/s.

Abstract: The present invention describes a process for the separation of xylenes in simulated counter-current utilising at least one adsorber with a limited cumulated total height (Hcu) of adsorbent and a superficial velocity (Vsl) of less than 2 cm/s.

Abstract: The present invention relates to a process for separating isomers by simulated moving bed (SMB) adsorption, comprising separating the raw materials comprising isomers by SMB adsorption, said SMB comprising many adsorption beds each of which is equipped with grids, each of the grids being equipped with the feedstock inlet and outlet pipeline of the bed, the feedstock charged into and discharged from SMB at least comprising feedstocks, desorbent, extract, and raffinate, the extract being enriched with the target product, characterized in that the extract is used as a flushing liquid and respectively charged to first or second bed at the upstream of the feedstock charging position and to one of second to fourth beds at the downstream of the extract withdrawing position. Such process is used for separation of C8 aromatic isomers by adsorption, and can improve the capacity of the device while effectively increasing the purity of the target product separated by adsorption.

Abstract: The invention relates to aggregate zeolitic adsorbents based on faujasite X type zeolite powder having a low silica content and small crystals, exchanged with barium or based on faujasite X type zeolite having a low silica content and small crystals, exchanged with barium and potassium. The invention also relates to the method for preparing said aggregate zeolitic adsorbents, and also their uses for separating sugars, polyhydric alcohols, isomers of substituted toluene, cresols, or for recovering very high purity paraxylene.

Abstract: A device (SMB) for separation by simulated moving bed adsorption comprises a plurality of elementary adsorption zones Zi in series operating in a closed loop, and at least one singular adsorption zone with a dead volume which is greater than the adsorption zones Zi, the solid adsorbant of said singular adsorption zone having a granulometry which is lower than that of the solid adsorbant of the ordinary adsorption zones.

Abstract: A method for separating a xylene from a feed mixture by contacting the feed mixture with a bed of adsorbent comprising metal organic framework crystals selective to the xylene.

Abstract: A process for separating para-xylene from a plurality of aromatic compounds, wherein the process introduces a mixed xylene feed stream comprising a plurality of xylene isomers into a first separation assembly to produce a first para-xylene enriched stream and a first raffinate stream. The process further feeds the raffinate stream into an isomerization unit to convert the raffinate stream into an isomerization reactor product stream, and introduces the isomerization reactor product stream into to a second para-xylene adsorptive separation unit to produce a second para-xylene enriched stream and a second raffinate stream.

Abstract: A process for the production of para-xylene by simulated counter-current adsorption with high flexibility with respect to a reference run (100%) uses 2 adsorbers each with 12 beds, said adsorbers being able to be connected in accordance with 3 different modes; the flexibility obtained is 50% to 150%.

Abstract: The invention concerns a device for distributing fluids which are to supply a multi-stage column having a succession of plates, each plate supporting a bed of granular solid (2) and being provided with a network for distributing said fluids constituted by substantially horizontal lines (6) having a plurality of degrees of branching from 1 to rank N, the ensemble of lines from rank P to rank N being adherent to the base plane of the plate under consideration, and the lines of the last degree of branching N communicating with mixing chambers (8) disposed immediately below said base plane.

Abstract: An aromatics complex producing one or more xylene isomers offers a large number of opportunities to conserve energy by heat exchange within the complex. One previously unrecognized opportunity is through providing two parallel distillation columns operating at different pressures to separate C8 aromatics from C9+ aromatics. The parallel columns offer additional opportunities to conserve energy within the complex through heat exchange in associated xylene recovery facilities.

Abstract: Adsorbents and methods for the adsorptive separation of para-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 zeolite X having an average crystallite size of less than 1.8 microns. The adsorbents provide improved mass transfer, which is especially advantageous for improving productivity in low temperature, low cycle time adsorptive separation operations in a simulated moving bed mode.

Abstract: This invention relates to a method of efficiently producing a high-purity para-substituted aromatic hydrocarbon while suppressing caulking without requiring isomerization-adsorption separation steps, and more particularly to a method of producing a para-substituted aromatic hydrocarbon, characterized in that a methylating agent and an aromatic hydrocarbon are reacted in the presence of a catalyst formed by coating MFI type zeolite having a particle size of not more than 100 ?m with a crystalline silicate.

Abstract: A process for separating a product from a multicomponent feedstream to an adsorption apparatus or system. The apparatus or system may comprise a moving-bed or a simulated moving-bed adsorption means. The product comprises at least one organic compound, such as an aryl compound with alkyl substitutes. In embodiments the conduits used to supply the feedstream to the apparatus or system are flushed with media of multiple grades. In embodiments the process achieves improvements in one or more of efficiency of adsorption separation, capacity of adsorption apparatus systems, and purity of product attainable by adsorption process.

Abstract: A process for separating a product from a multicomponent feedstream to an adsorption apparatus or system is described. The apparatus or system may comprise a moving-bed or a simulated moving-bed adsorption means. The product comprises at least one organic compound, such as an aryl compound with alkyl substitutes. In embodiments the conduits used to supply the feedstream to the apparatus or system are flushed with media of multiple grades. The improvement is a more efficient use of the desorbent. In embodiments the process achieves improvements in one or more of efficiency of adsorption separation, capacity of adsorption apparatus systems, and purity of product attainable by adsorption process.

Abstract: A process for separating a product from a multicomponent feedstream to an adsorption apparatus or system is described. The apparatus or system may comprise a moving-bed or a simulated moving-bed adsorption means. The product comprises at least one organic compound, such as an aryl compound with alkyl substitutes. In embodiments the conduits used to supply the feedstream to the apparatus or system are flushed with media of multiple grades. The improvement is more efficient use of the desorbent. In embodiments the process achieves improvements in one or more of efficiency of adsorption separation, capacity of adsorption apparatus systems, and purity of product attainable by adsorption process.

Abstract: A process for separating para-xylene from aromatic compounds is presented. The process introduces throughout a first step-time interval a first mixed xylene stream into a first feed input on a first adsorptive separation unit comprising multiple bed lines. The process further introduces throughout the first step-time interval a second mixed xylene stream into a second feed input on the first adsorptive separation unit. During a first portion of the first step-time interval, the process introduces material from a feed stream used during the first step-time interval into a bed line not used to deliver a stream into, or withdraw a stream from, the first adsorptive separation unit during the first step time interval. During a second portion of the first step-time interval, the process introduces material from a purification zone into the feed stream used during the first step-time interval.

Abstract: A process for separating a product from a multicomponent feedstream to an adsorption apparatus or system. The apparatus or system may comprise a moving-bed or a simulated moving-bed adsorption means. The product comprises at least one organic compound, such as an aryl compound with alkyl substitutes. In embodiments the conduits used to supply the feedstream to the apparatus or system are flushed with media of multiple grades. In embodiments the process achieves improvements in one or more of efficiency of adsorption separation, capacity of adsorption apparatus systems, and purity of product attainable by adsorption process.

Abstract: The present invention relates to agglomerated zeolitic adsorbents based on zeolite X with an Si/Al ratio such that 1.15<Si/AL<1.5, consisting of crystals with a mean diameter of 1.7 mm or less and of an inert binder, at least 90% of the exchangeable cationic sites of the zeolite X being occupied by barium ions. They may be obtained by agglomerating a zeolite X powder having a mean diameter of 1.7 mm or less with a binder, followed by zeolitization of the binder, exchange of the zeolite ions with barium (and potassium) ions and activation of the adsorbents thus exchanged.

Abstract: A process of producing PX comprising providing a C8+ feedstock, the C8+ feedstock has C8 hydrocarbons and C9+ hydrocarbons, to a crystallization unit under crystallization conditions to produce a PX enriched stream having a PX concentration of at least 99.5 wt % based on the weight of the PX enriched stream, wherein the C8+ feedstock has a PX concentration of at least 70 wt % based on total weight of xylenes in the C8+ feedstock, which the C8+ feedstock having a C9+ hydrocarbons concentration in a range from 1 wppm to 10 wt % based on the total weight of the C8+ feedstock.

Abstract: There is provided a closed loop purity and recovery control system and process for operating a xylene purification system such as a Parex unit.

Abstract: A process according to various approaches includes flushing residual fluid within an intermediate transfer line of a purification zone between a feed stream transfer line and the extract stream transfer line away from the adsorptive separation chamber to remove at least a portion of the residual fluid from the intermediate transfer line. The process may include directing the residual fluid flushed from the intermediate transfer line to another intermediate transfer line of the purification zone to flush residual fluid of the other transfer line into the purification zone for separation of the preferentially adsorbed component from the non-preferentially adsorbed component present in the other transfer line residual fluid.

Abstract: The present process comprises a means for energy savings in one or more process pumps by driving the one or more pumps with a variable-speed driving means. The invention is particularly useful in the separation of an adsorbed product from a mixture of components using simulated-moving-bed adsorption associated with a large circulating stream pumped with variable-speed driving means 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.