abstract |
The cost of separating para-xylene from other xylene isomers and C 9 aromatics by adsorption on zeolitic molecular sieves is reduced by the use of 1,4 diisopropylbenzene as a relatively high boiling desorbent. The desorbent has surprisingly high strength and selectivity characteristics with the preferred desorbent. The preferred adsorbent is an X zeolite containing barium or both barium and potassium ions at exchangeable cationic sites. The para-xylene components are selectively adsorbed onto the adsorbent. The non-adsorbed feed is then removed from the adsorbent and the para-xylene recovered by desorption. |