Process for the production and recovery of ortho-xylene,para-xylene and ethylbenzene

Abstract

Abstract A MODIFIED DUAL ADSORPTION AND ISOMERIZATION PROCESS EMPLOYING A COMBINATION OF AN ORTHO-XYLENE SEPARATION ZONE AND A FIRST ADSORPTION ZONE IN COMMUNICATION WITH A SECOND ADSORPTION ZONE AND AN ISOMERIZATION ZONE. THE PROCESS IS SUITABLE FOR THE SEPARATION OF VARIOUS C8 AROMATIC ISOMERS INTO INDIVIDUAL RELATIVELY PURE STREAMS CONTAINING THE INDIVIDUAL ISOMERS. THE ORTHO-XYLENE SEPARATION ZONE SEPARATES ORTHO-XYLENE FROM THE OTHER C8 AROMATIC ISOMERS CONTAINED IN THE FRESH FEED AND RECYCLE FEED AND PASSES THE REMAINING C8 AROMATIC ISOMERS TO A FIRST ADSORPTION ZONE. THE FIRST ADSORPTION ZONE THEN SEPARATES PARA-XYLENE AND ETHYLBENZENE FROM META-XYLENE AND PASSES THE PARA-XYLENE AND ETHYLBENZENE TO A SECOND ADSORPTION ZONE WHEREIN PARA-XYLENE AND ETHYLBENZENE ARE SEPARATED INTO RELATIVELY PURIFIED PARA-XYLENE AND ETHYLBENZENE STREAMS. THE REMAINING META-XYLENE SEPARATED FROM THE PARA-XYLENE IN THE FIRST ADSORPTION ZONE IS PASSED INTO AN ISOMERIZATION ZONE TO EFFECT THE PRODUCTION OF ADDITIONAL C5 AROMATIC ISOMERS WHICH ARE RECYCLED TO AND SEQUENTIALLY SEPARATED BY THE ORTHO-XYLENE SEPARATION ZONE AND THE FIRST AND SECOND ADSORPTION ZONES, ALLOWING INCREASED YIELDS OF SOME OF THE C8 AROMATICS BASED ON FRESH FEED TO THE ORTHO-XYLENE ZONE. THE MODIFICATION BASICALLY COMPRISES SEPARATING AND REMOVING ORTHO-XYLENE FROM THE FEED TO THE ISOMERIZATION ZONE THUS ALLOWING THE PRODUCTION OF ADDITIONAL ORTHO-XYLENE IN SAID ZONE AND THEREBY RESULTING IN A HIGHER OVERALL YIELD OF ORTHO-XYLENE BASED ON FRESH FEED THAN THAT RESULTING IF ORTHO-XYLENE WERE NOT SEPARATED AND REMOVED.

Inventors

• 👤 Laurence O Stine
• 👤 Donald B Broughton

Bibliographic Details