Continuous process and device for the chromatographic separation of a

Abstract

A process and a device are described for the continuous separation, in the fluid phase, of a mixture of at least three constituents into three fractions. A so-called simulated countercurrent technique is used in a separation column packed with a sorbent having five zones 6, 5, 4, 3 and 2 with different functions, and the following sequence of steps is performed: so-called strong solvent S.sub.2 is introduced, a strong solvent extract E.sub.2 is removed, the same solvent is introduced but at a lower temperature and/or at a lower pressure (so-called weak solven S.sub.1), weak solvent extract E.sub.1 is drawn off, the mixture to be separated is introduced, weak solvent raffinate R is drawn off and a stream Roy is recycled alternately to the feed for strong solvent S.sub.2 and then to the feed for weak solvent S.sub.1. A stream coming from zone 6 is sent alternately to an outlet for storng solvent extract E.sub.2 and then to the inlet of the fifth zone. The various feeds and draw-offs are periodically caused to advance synchronously through the column. Application especially to the separation of glucose, xylose and arabinose and to the purification of water containing phenol, paracresol and toluene.