Abstract: A pressure swing adsorption process to separate para-xylene and ethylbenzene from C8 aromatics which uses a para-selective, non-acidic, medium pore molecular sieve of the MFI structure type and is operated isothermally in the vapor phase at elevated temperatures and pressures is integrated with crystallization to produce para-xylene product. A fixed bed of adsorbent is saturated with pX and EB, which are preferentially adsorbed, the feed is stopped, and lowering the partial pressure desorbs the pX and EB. The process effluent, which is rich in pX and EB, is crystallized to obtain para-xylene product.
Type:
Grant
Filed:
July 10, 2001
Date of Patent:
July 29, 2003
Assignee:
BP Corporation North America Inc.
Inventors:
Ruth Ann Doyle, Jeffrey T. Miller, Richard A. Wilsak, Scott A. Roberts, Giorgio Zoia