Abstract: A simulated moving bed (SMB) separation device comprising a column, beds Ai of adsorbent separated by plates Pi with a single distribution and extraction network for fluids, in particular feed F, desorbant D, raffinate R and extract B, and a plurality of two-way valves for distribution of said fluids, said valves being limited in number compared with the prior art. The column is divided into a plurality of sectors Sk with 2 or 3 superimposed plates, each sector Sk comprising an external bypass line Lk connected to each plate Pi of Sk via a connector comprising a plate valve Vi. Each line Lk comprises a controlled means for limiting its internal flow, and is connected to each of the fluid networks F, D, R, E via a single line comprising a single controlled two-way isolation valve to supply for sequential supply or withdrawal of the corresponding fluid F, D, R or E towards or from the sector Sk under consideration.

Abstract: The invention concerns a simulated moving bed adsorption separation device comprising a limited number of large diameter valves. According to the invention, the device comprises a column with a plurality of sectors Sk with 2 superimposed plates Pi with a single distribution network, each sector Sk comprising an external principal bypass line Lk connected to each plate Pi of Sk via a large diameter plate valve Vi and an external secondary bypass line Mk comprising a small diameter valve VMk connected to the adjacent sector Sk?1. Each line Lk comprises a flow rate limitation means and is connected to each fluid network via a single large diameter valve. Further, the connectors of lines Lk onto the column are offset by at most 20° inside Sk to limit the volume of lines Lk, and are offset by a mean angle in the range 70° to 110° between two neighbouring sectors Sk and Sk+1 so as not to weaken the column mechanically.

Abstract: Process for the production of paraxylene from a C8 aromatic feedstock that comprises the following stages: A stage for separation by adsorption in a simulated moving bed SMB that produces an extract that contains at least 95% paraxylene and at least one raffinate R that contains ethylbenzene, A recycling of raffinate to the SMB separation stage after isomerization, in which R is separated in membrane separation means to obtain a first fraction F1 that is relatively high in ethylbenzene, which is purged, and an additional fraction F2 that is relatively low in ethylbenzene, which is recycled to the SMB after a single isomerization, preferably in the liquid phase.

Abstract: Process for separation of metaxylene, with at least 99% by weight of purity of an aromatic feedstock F, in a single adsorption stage in a simulated moving bed in an SMB device that comprises 12, 13 or 15 adsorbent beds with different numbers of beds being employed in zone 1 between the supply of the desorbent D and the draw-off of the extract E; zone 2 between the draw-off of the extract E and the supply of the feedstock F; zone 3 between the supply of the feedstock and the draw-off of the raffinate R; and zone 4 between the draw-off of the raffinate R and the supply of the desorbent D whereby the process is carried out according to a configuration of zones (a, b, c, d), whereby a, b, c, and d represent the number of adsorbent beds that operate respectively in zones 1, 2, 3, 4 in which there is used: Either an SMB of 12 adsorbent beds operating according to the configuration (2, 5, 3, 2), Or an SMB of 13 adsorbent beds operating according to the configuration (2, 5, 4, 2), Or an SMB of 15 adsorbent beds op

Abstract: Process for separating paraxylene with a purity that is at least equal to 99.5% by weight from an aromatic feedstock F in a single adsorption stage in a simulated moving bed (SMB), comprising different numbers of beds, allocated to a zone 1 between the supply of the desorbent D and the draw-off of the extract E; a zone 2 between the draw-off of the extract E and the supply of the feedstock F; a zone 3 between the supply of the feedstock and the draw-off of the raffinate R; a zone 4 between the draw-off of the raffinate R and the supply of the desorbent D, wherein an SMB of 12 adsorbent beds has bed configuration (2, 5, 3, 2), an SMB of 15 adsorbent beds has bed configuration (3, 6, 4, 2), or an SMB of 19 adsorbent beds has bed configuration (4, 7, 6, 2), wherein the desorbent in this latter case is paradiethylbenzene.

Abstract: The invention concerns a process for separating meta-xylene from a hydrocarbon feed comprising isomers containing 8 carbon atoms, comprising: a step for bringing said feed into contact with a faujasite type zeolite adsorbant, the water content of the adsorbant being in the range 0 to 1% by weight and the adsorption temperature being from 160° C. to 180° C.; a desorption step employing a solvent selected from toluene, indane and mixtures thereof.

Abstract: The invention concerns a process for producing high purity meta-xylene, comprising a step for separation by simulated moving bed adsorption starting from an aromatic C8 feed delivering a fraction which is rich in meta-xylene and a fraction which is depleted in meta-xylene, and a step for crystallization of the meta-xylene rich fraction. The purity of the meta-xylene produced is at least 99.5%.

Abstract: A process for producing para-xylene from a hydrocarbon feed is described in which an adsorption column operating as a simulated moving bed with at least five zones delivers an extract, a 2-raffinate and an intermediate raffinate. The extract is distilled and the distillate is optionally re-crystallized to recover para-xylene with a purity of at least 99.7%. The 2-raffmate is distilled then isomerized in a reactor preferably operating in the liquid phase and at a low temperature. The intermediate raffinate with an enriched ethylbenzene content is distilled then isomerized in the vapour phase.

Abstract: The invention concerns a simulated moving bed adsorption separation device comprising a limited number of valves. According to the invention, the device comprises a column with a plurality of sectors Sk with 2 superimposed plates Pi with a single distribution network, each sector Sk comprising an external principal bypass line Lk connected to each plate Pi of Sk via a plate valve Vi. Each line Lk comprises a flow limitation means and is connected to each of the fluid networks via a single valve. Further, the connectors of lines Lk onto the column are offset by at most 20° inside Sk to limit the volume of lines Lk, and are offset by a mean angle in the range 70° to 110° between two neighbouring sectors Sk and Sk+1 so as not to weaken the column mechanically. The plates preferably comprise panels DMEi,j with parallel segments the direction of which varies from plate to plate or per group of 2 plates.

Abstract: The invention concerns a simulated moving bed adsorption separation device comprising a limited number of large diameter valves. According to the invention, the device comprises a column with a plurality of sectors Sk with 2 superimposed plates Pi with a single distribution network, each sector Sk comprising an external principal bypass line Lk connected to each plate Pi of Sk via a large diameter plate valve Vi and an external secondary bypass line Mk comprising a small diameter valve VMk connected to the adjacent sector Sk?1. Each line Lk comprises a flow rate limitation means and is connected to each fluid network via a single large diameter valve. Further, the connectors of lines Lk onto the column are offset by at most 20° inside Sk to limit the volume of lines Lk, and are offset by a mean angle in the range 70° to 110° between two neighbouring sectors Sk and Sk+1 so as not to weaken the column mechanically.

Abstract: The invention concerns a simulated moving bed (SMB) separation device and process comprising a column, beds Ai of adsorbent separated by plates Pi with a single distribution and extraction network for fluids, in particular feed F, desorbant D, raffinate R and extract E, and a plurality of two-way valves for distribution of said fluids, said valves being limited in number and in particular with dimensions that are smaller than in the prior art. According to the invention, the column is divided into a plurality of sectors Sk with 2 superimposed plates, each sector Sk comprising an external principal bypass line Lk connected to each plate Pi of Sk via a large diameter plate valve Vi and an external secondary bypass line Mk comprising a small diameter valve VMk connected to the adjacent sector Sk?1.

Abstract: The invention concerns a simulated moving bed (SMB) separation device comprising a column, beds Ai of adsorbent separated by plates Pi with a single distribution and extraction network for fluids, in particular feed F, desorbant D, raffinate R and extract E, and a plurality of two-way valves for distribution of said fluids, said valves being limited in number compared with the prior art. According to the invention, the column is divided into a plurality of sectors Sk with 2 or 3 superimposed plates, each sector Sk comprising an external bypass line Lk connected to each plate Pi of Sk via a connector comprising a plate valve Vi. Each line Lk comprises a controlled means for limiting its internal flow, and is connected to each of the fluid networks F, D, R, E via a single line comprising a single controlled two-way isolation valve to supply for sequential supply or withdrawal of the corresponding fluid F, D, R or E towards or from the sector Sk under consideration.

Abstract: The invention concerns a process for separating meta-xylene from a hydrocarbon feed comprising isomers containing 8 carbon atoms, comprising: a step for bringing said feed into contact with a faujasite type zeolite adsorbant, the percentage of water in the adsorbant being in the range 0 to 8% by weight and the adsorption temperature being from 25° C. to 250° C.; a desorption step employing a solvent selected from tetraline and its alkylated derivatives; a step for separating meta-xylene from the desorbant.

Abstract: The invention concerns a process for separating meta-xylene from a hydrocarbon feed comprising isomers containing 8 carbon atoms, comprising: a step for bringing said feed into contact with a faujasite type zeolite adsorbant, the water content of the adsorbant being in the range 0 to 1% by weight and the adsorption temperature being from 160° C. to 180° C.; a desorption step employing a solvent selected from toluene, indane and mixtures thereof.

Abstract: A process for adsorption separation uses a solid IM-12 type adsorbent to separate a molecular species from any feed.

Abstract: A process for co-producing para-xylene and styrene from a feed (1) of hydrocarbons containing xylenes and ethylbenzene is described, the process comprising the following succession of steps: a step for separating the feed in a simulated moving bed in an adsorption column (6) containing beds of an adsorbent, from which an extract that is rich in para-xylene (7a) of at least 99.7% purity and at least one raffinate (7b) containing ethylbenzene, ortho-xylene, meta-xylene and a very small quantity of para-xylene is withdrawn; a step for dehydrogenating (10) the ethylbenzene contained in the raffinate (7b) to styrene; at least one step for primary separation of the stream (11) from the dehydrogenation step (10), to eliminate by-products; a step for separating the purified mixture (18) derived from the stream (11) containing styrene, unconverted ethylbenzene, meta-xylene and ortho-xylene, from which a stream (21a) that is rich in styrene of at least 99.

Abstract: A process for co-production of paraxylene, metaxylene and/or orthoxylene from a hydrocarbon feedstock (1) that comprises [1] a separation stage of the feedstock in a simulated moving bed in a chromatographic column (9) that contains a number of beds of an adsorbent, interconnected in a loop, is described, whereby said column comprises an injection (3) of the feedstock, a draw-off (10) of an extract that consists of paraxylene and desorbent, an intermediate fraction (11) (extract or raffinate) that contains ethylbenzene, and a raffinate (12) that contains a mixture of metaxylene and orthoxylene that is virtually free of ethylbenzene and paraxylene and [2] a crystallization stage (27) of the metaxylene and/or orthoxylene fraction. Upstream from the adsorption zone and/or upstream from the crystallization zone, it is possible to distill the entering mixture to produce an orthoxylene-enriched fraction at the bottom and a metaxylene-enriched fraction at the top.

Abstract: A process is described for co-producing metaxylene and paraxylene from a hydrocarbon feed comprising two separation steps. The first step of the process is a counter-current simulated moving bed system in a chromatographic column containing at least five zones, comprising injecting the feed and injecting a desorbent and delivering an extract, a raffinate and an intermediate raffinate either continuously or discontinuously. The extract is distilled to obtain a paraxylene with a purity of at least 99.7%. The raffinate, which is richer in metaxylene, is distilled to extract the desorbent and injected into a counter-current simulated moving bed continuously delivering an extract and a raffinate. One of these two streams is enriched in metaxylene. The most metaxylene-rich stream is distilled to obtain metaxylene with a purity of more than 99%.

Abstract: A coproduction process for ortho-xylene and para-xylene starting with a batch of hydrocarbons comprises a simulated counter-current fluidized bed system in a chromatographic column (6) containing at least five zones, comprising injection (1) of the batch and injection (2) of desorption agent and delivering an extract (3), a refined product (5), and an intermediate refined product (4). Refined product (5), richer in ortho-xylene than the intermediate refined product, is distilled (9) to extract desorption agent (15) and is injection, according to the second step of the process, into a simulated counter-current fluidized bed system (17) delivering an extract (18) and a refined product (19) continuously.

Abstract: A coproduction process for ortho-xylene and para-xylene starting with a batch of hydrocarbons comprising two separation steps is described. The first step relates to a simulated counter-current fluidized bed system in a chromatographic column (6) containing at least five zones, comprising injection (1) of the batch and injection (2) of desorption agent and delivering an extract (3), a refined product (5), and an intermediate refined product (4). The extract is distilled (7) to obtain para-xylene (10) that is very pure or that can be purified by crystallization. The refined products are withdrawn continuously or discontinuously. Refined product (5), richer in ortho-xylene than the intermediate refined product, is distilled (9) to extract desorption agent (15) and is injected, according to the second step of the process, into a simulated counter-current fluidized bed system (17) delivering an extract (18) and a refined product (19) continuously.