Carbon Molecular Sieve Membranes Comprising Graphene Oxides and Porous Carbon for CO(2)/N(2) Separation

To improve the CO(2)/N(2) separation performance, mixed-matrix carbon molecular sieve membranes (mixed-matrix CMSMs) were fabricated and tested. Two carbon-based fillers, graphene oxide (GO) and activated carbon (YP-50F), were separately incorporated into two polymer precursors (Matrimid(®) 5218 and ODPA-TMPDA), and the resulting CMSMs demonstrated improved CO(2) permeability. The improvement afforded by YP-50F was more substantial due to its higher accessible surface area. Based on the gas permeation data and the Robeson plot for CO(2)/N(2) separation, the performances of the CMSMs containing 15 wt % YP-50F and 15 wt % GO in the mixed polymer matrix surpassed the 2008 Robeson upper bound of polymeric membranes. Hence, this study demonstrates the feasibility of such membranes in improving the CO(2)/N(2) separation performance through the appropriate choice of carbon-based filler materials in polymer matrices.