Recovery of gases, especially permanent gases, from streams of matter, especially from offgas streams from polymerizations

摘要

A method of cleaning a stream of matter that includes a C2+ fraction and a first gaseous substance and a second gaseous substance. The stream of matter is subjected to a pressure swing adsorption to remove the C2+ fraction by means of a membrane to obtain a retentate and a permeate. The first substance is enriched in retentate and depleted in permeate and the second substance is depleted in retentate and enriched in permeate.