Patent ID: 8715397
Filing Date: 2014-05-06
Classification: B01D,Y02C

Abstract:
1. A cyclic process for separating CO 2 from a gas stream, which process comprises: dehumidifying the gas stream to remove substantial quantities of water therefrom; contacting the dehumidified gas stream with an absorbent system comprising a non-aqueous aprotic solvent, an amine CO 2 sorbent, and a non-nucleophilic base having a pK a at least 3 units higher than that of the amine at a temperature above 50° C. to sorb CO 2 , wherein the contacting of the absorbent system with the dehumidified gas stream results in formation of a stabilized mixed carbamate in which the CO 2 forms a carbamate by reaction with the amine sorbent and in which a protonated form of the non-nucleophilic base forms a stabilizing counterion for the carbamate; and treating the absorbent system containing the sorbed CO 2 under conditions sufficient to cause desorption of at least a portion of the CO 2 .