Continuous process and device for the chromatographic separation of a mixture of at least three constituents into three purified effluents by means of a single solvent at two different temperatures and/or at two different pressures

摘要

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.PPA 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.PPApplication especially to the separation of glucose, xylose and arabinose and to the purification of water containing phenol, paracresol and toluene.