Patent ID: 6099736
Filing Date: 2000-08-08
Classification: B01D

Abstract:
A simulated moving bed separation process for a feed comprising at least 2 constituents in the presence of at least one solvent, in an apparatus containing n chromatographic column sections in a closed loop each capable of operating within z zones, z being at least 4, a recycling pump for a mixture of the solvent and constituents located between the nth and first sections and being operated in each zone successively during the course of one cycle, each of the n column sections including an introduction (inlet) or extraction (outlet) point corresponding to each zone such that there are a total of z.multidot.n introduction and extraction points, wherein the recycling pump circulates said mixture in a recycle flow rate Q.sub.c which is substantially constant during the cycle, said flow rate Q.sub.c being greater than all other flow rates introduced or extracted to/from the apparatus, and wherein all the introduction and extraction points are shifted throughout the cycle simultaneously and the time between successive shifts is non-constant, such that the eluted volume at the outlet to each zone is substantially constant, zone by zone, between two successive shifts throughout the cycle.