Normal butane/iso-butane separation

摘要

Iso-butane is separated from normal butane in a pressure swing adsorption system of at least three adsorbent beds, each adapted to selectively adsorb normal butane from a mixture thereof with iso-butane. The adsorption front of normal butane formed in each adsorbent bed upon the passage of the feed gas mixture thereto is moved through the bed to an extent enhancing the utilization of the adsorptive capacity thereof. By combinations of depressurization and repressurization together with purge, desirable product purity levels are obtained, while the costs of adsorbent equipment and of operation are reduced to the extent possible consistent with the purity requirements of a given application.