USE OF ENZYME CATALYSTS IN CO2 PCC PROCESSES

摘要

A method for processing a stream enriched in CO2 from a gas by the action of an absorbent in the stream includes desorbing CO2 from the stream by application of heat to the stream to desorb the CO2 and regenerate the absorbent in a reaction system that includes reconstitution of carbon dioxide and an alkanolamine from carbamate and ammonium ion solution. The energy requirement for the aforementioned reconstitution is materially reduced by the presence of a biocatalyst. The biocatalyst may be selected for its activity in cleaving urethane bonds to effect release of CO2 and an amine. In another aspect, a gas stream is contacted with a sorbent system to effect absorption of CO2 from the gas stream, the sorbent and absorbed CO2 are separated from the gas stream to form a CO2-rich stream, and the sorbent system contains a primary or secondary alkanolamine and a catalyst selected to modify the reaction kinetics of the absorption process so as to materially increase the proportion of bicarbonate in the CO2-rich stream relative to carbamate.