Patent ID: 6379554
Filing Date: 2002-04-30
Classification: B01D,G01N

Abstract:
In a simulated moving bed process for the recovery of a first product fraction predominating in a first product species from a liquid mixture containing said first product species in admixture with a second byproduct species, wherein a feed stock is introduced to a recycle stream circulating through a partitioned bed of resin, raffinate is withdrawn from said recycle stream downstream from the introduction of said feed stock, eluent is introduced to said recycle stream downstream from the withdrawal of said raffinate, and extract is withdrawn from said recycle stream downstream from the introduction of said eluent, the improvement comprising: establishing a first continuous simulated moving bed system in which:a first feed stock, comprising a relatively large amount of said first product species and a relatively small amount of said second byproduct species, is introduced into a first recycle stream circulating through a first partitioned bed of resin; a first raffinate, comprising separated said first product species and containing other contaminant species, is withdrawn from said first recycle stream downstream from the introduction of said first feed stock; eluent is introduced to said first recycle stream downstream from the withdrawal of said first raffinate; and a first extract, comprising separated said second byproduct species, is withdrawn from said first recycle stream downstream from the introduction of said eluent; and establishing a second chromatographic separation procedure in which said first raffinate is contacted by a second resin bed to produce: a second raffinate, comprising said other contaminant species from said first raffinate; and a second extract, predominating in said first product species from said first raffinate at a high purity.