Process for the separation by adsorption of 2,6- or 3,5-diethyltoluene from a mixture thereof with another diethyltoluene isomer.

摘要

3,5-diethyltoluene (3,5-DET) and/or 2,6-diethyltoluene (2,6-DET) is selectively separated from a feed mixture comprising at least one isomer from the group 3,5-DET or 2,6-DET and at least one other DET isomer by contacting the feed mixture at adsorption conditions with an adsorbent selected from the Groups consisting of A) X zeolite exchanged with a potassium cation; B) X zeolite exchanged with sodium or copper or Y zeolite exchanged with copper, sodium, barium or calcium; and C) X zeolite exchanged with barium or lithium or with potassium and barium or Y zeolite exchanged with potassium, sodium, barium or calcium, thereby selectively adsorbing one of the DET isomers contained in the feed; thereby selectively adsorbing one or more of said DET isomers and removing one or more relatively non-adsorbed isomer(s) from contact with the adsorbent to form a raffinate stream depleted in the adsorbed isomer relative to feed and thereafter contacting the rich adsorbent with a desorbent comprising a monocyclic alkyl-substituted aromatic hydrocarbon at desorption conditions effective to form an extract stream enriched in the adsorbed isomer relative to the feed.