Self-enhancement of CO reversible absorption accompanied by phase transition in protic chlorocuprate ionic liquids for effective CO separation from N2

Abstract

An efficient strategy for the high-capacity capture of CO is reported, and a phase change in protic chlorocuprate ionic liquids (PCILs) from liquid to solid is found during CO absorption. The highest CO capacity is 0.96 mol_CO mol_IL⁻¹, being at least 150 times higher than that in [BMIM][PF₆]. Both absorption and membrane permeation reveal that the PCILs are potential for the selective separation of CO from N₂.