There have been advances in zeolitic-imidazolate frameworks (ZIFs), a subclass of metal-organic frameworks (MOFs), that have allowed them to be useful for carbon dioxide separation from flue gas streams. Extensive modeling has been performed to demonstrate the value of using MOFs as membranes. MOF materials are adsorption-based, and thus can be tuned to achieve selectivity. The drawback to MOF systems is stability in water and other compounds present in flue gas streams. Select materials, such as ZIF-8, have demonstrated stability in water and benzene, contents often present in flue gas mixtures. ZIF-8 can be synthesized as a membrane on a porous alumina support and has proven to be effective at separating CO2 from flue gas streams. At similar CO2/CH4 selectivity to Y-type zeolite membranes, ZIF-8 membranes achieve unprecedented CO2 permeance, two orders of magnitude above the previous standard.