Highly permeable and selective graphene oxide-enabled thin film nanocomposite for carbon dioxide separation

Abstract

Membrane technology appeals as an environmental friendly approach for CO2 capture application due to its modest energy requirement and scalability but high performing membranes are constantly sought after to make this technology economically competitive to the conventional amine absorption process. This study focuses on a relatively new class of membrane known as the thin film nanocomposite (TFN) which is characterized with extremely thin selective layer for high productivity. Using the interfacial polymerization (IP) technique, TFNs embedded with graphene oxide (GO) were successfully fabricated to investigate the effects of GO loading on the morphology and gas separation performance of the resultant membrane. Permeance and selectivity of the TFN is a positively correlated with GO content. The optimum sample, TFN-0.5 exhibited more than twice the CO2 permeance of neat thin film composite (TFC) while achieving CO2/N2 and CO2/CH4 separation factor of 41 (26% increment) and 25 (26% increment) respectively. The enhancement in TFN performance was attributed to the increased tortuosity in polymer matrix and the introduction of rapid diffusion passages resulted from incorporation of rigid GO sheets. GO-TFN demonstrated attractive potential for low pressure post-combustion CO2 separation to reduce emission of the greenhouse gas and mitigate the global warming issue.