921 results about "Simulated moving bed" patented technology

A plurality of chromatographic separation operations, including a first simulated moving bed operation, are coupled into a process which functions, preferably through the application of continuous displacement chromatography, to recover a fraction rich in small organic molecules, notably betaine and / or invert from sucrose solutions, enabling the subsequent production of a high purity sucrose product.

Product purity from or capacity of a simulated-moving-bed adsorptive separation process is increased by flushing the contents of the transfer line previously used to remove the raffinate stream away from the adsorbent chamber, preferably into the raffinate column used to separate desorbent from raffinate product. Preferably a stream from the adsorbent chamber at an intermediate point between the feed entry point and raffinate withdrawal is used as the flushing liquid. This flush step eliminates the passage of a quantity of the raffinate material into the adsorbent chamber in the transfer-line flush period or when the process conduit is subsequently used to charge the feed stream to the adsorbent chamber.

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 small-crystallite-size zeolite X having an average crystallite size of less than 1.8 microns. The adsorbents may be binderless (e.g., formulated with the substantial absence of an amorphous material that normally reduces selective pore volume) to further improve capacity and mass transfer. These properties are especially advantageous for improving productivity in low temperature, low cycle time adsorptive separation operations in a simulated moving bed mode.

Distributed valve simulated moving beds are described in which junctions located between successive columns interrupt the flow of process fluid between columns, and either transmit the process fluid through a zone bypass to a succeeding column within the same zone or, if the junction is located between zones, direct the process fluid to an input / output line that is dedicated to the particular zone that immediately follows the junction. At each step of the SMB's operation, the distribution of flows in each junction is modulated to accomplish movement of ports consistent with the SMB's design. Further described are simulated moving beds that contain one or more decoupled on-line regeneration zones. The regeneration zone is decoupled from the separation zones in the sense that it observes a step time (a “regeneration interval”) that is different than the step time observed by the separation zones of the SMB. Because the regeneration zone is “on-line,” the SMB need not be stopped to remove columns for regeneration. Because the regeneration zone is decoupled from the separation zones, the column can stay in the regeneration zone as long as needed to accomplish the regeneration, regardless of the step time observed by the SMB.

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 binderless adsorbents (e.g., formulated with the substantial absence of an amorphous material that normally reduces selective pore volume), particularly those with a water content from about 3% to about 5.5% by weight, improve capacity and / or mass transfer. These properties are especially advantageous for improving productivity in low temperature, low cycle time adsorptive separation operations in a simulated moving bed mode.

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-raffinate 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.

The present invention relates to a simulated moving bed process, wherein at least one adsorbent is washed after binding of target compound and wherein the outlet of wash liquid from the adsorbent is subsequently passed onto another adsorbent for binding of target compound removed by the washing. In one embodiment, the method comprises binding of at least one target compound using three or more adsorbents connected in series and elution of target compound from said three adsorbents. After the binding to an adsorbent, wash liquid is passed across the adsorbent to recover desorbed and / or unbound target compound, and the outlet of such wash liquid is directed to the adsorbent after the next in the series, to which no feed has yet been added. The target compound is recovered by eluting target compound from the washed adsorbents.

A system and method for separating and / or purification of CO2 gas from a CO2 feed stream is described. The system and method include a plurality of fixed sorbent beds, adsorption zones and desorption zones, where the sorbent beds are connected via valve and lines to create a simulated moving bed system, where the sorbent beds move from one adsorption position to another adsorption position, and then into one regeneration position to another regeneration position, and optionally back to an adsorption position. The system and method operate by concentration swing adsorption / desorption and by adsorptive / desorptive displacement.

The present invention relates to agglomerated zeolitic adsorbents containing zeolite X and an inert binder, the inert binder containing at least 80% by weight of clay which has undergone zeolitization by the action of an alkaline solution, the zeolite X having with an Si / Al ratio such that 1.15<Si / Al≦1.5, at least 90% of the exchangeable cationic sites of the zeolite X of which are occupied either by barium ions alone or by barium ions and potassium ions whose Dubinin volume is greater than or equal to 0.240 cm3 / g. They are obtained by agglomerating zeolite powder with a binder, followed by the zeolitization of the binder, the exchange of the ions of the zeolite by barium ions (and potassium ions) and the activation of the adsorbents thus exchanged. These adsorbents are particularly suited to the adsorption of the para-xylene present in C8 aromatic hydrocarbon fractions in the liquid phase in processes of simulated moving bed type but also to the separation of sugars, polyhydric alcohols, cresols or substituted toluene isomers.

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.