1356726 Separating m- and p-cymenes HERCULES Inc 9 Aug 1972 [10 Aug 1971] 37240/72 Heading C5E p- or m-cymene is separated from a mixture comprising p-cymene, m-cymene and, optionally, o-cymene by selective sorption on a molecular sieve zeolite. The mixture is preferably in the liquid phase. Suitable zeolites are type X or type Y, e.g. 13X based exchanged with Ba and K salts. The sorbed cymene isomer may be displaced by a desorbent, e.g. benzene or toluene. A simulated moving bed scheme is described involving 4 zones of sorbent connected in series to which the feed mixture and desorbent are introduced and the extract and raffinate are removed, these inlets and outlets to the 4 zones being cyclically changed. The extract and the raffinate may each be distilled to recover m- and p-cymenes.
展开▼
