Recovery of co-adsorbed hydrocarbons from molecular sieve adsorption units

摘要

In the purification of light hydrocarbons to remove carbonyl sulfide impurity by selective adsorption thereof on molecular sieve adsorbents, significant losses of the hydrocarbon are incurred by its coadsorption on the adsorbent with the COS impurity. Conventional desorption procedures produce a desorbate which is a non-commercial mixture of COS and hydrocarbon. The purge desorption method of the present invention utilizing a mixture of CO.sub.2 and a non-sorbable purge gas permits recovery of the coadsorbed hydrocarbon in a pure and commercially useful form.