A grand canonical Monte Carlo study of SO capture using functionalized bilayer graphene nanoribbons.

Grand canonical Monte Carlo (GCMC) simulation is used to study the adsorption of pure SO using a functionalized bilayer graphene nanoribbon (GNR) at 303 K. The functional groups considered in this work are OH, COOH, NH, NO, and CH. The mole percent of functionalization considered in this work is in the range of 3.125%-6.25%. GCMC simulation is further used to study the selective adsorption of SO from binary and ternary mixtures of SO, CO, and N, of variable composition using the functionalized bilayer graphene nanoribbon at 303 K. This study shows that the adsorption and selectivity of SO increase after the functionalization of the nanoribbon compared to the hydrogen terminated nanoribbon. The order of adsorption capacity and selectivity of the functionalized nanoribbon is found to follow the order COOH > NO > NH > CH > OH > H. The selectivity of SO is found to be maximum at a pressure less than 0.2 bar. Furthermore, SO selectivity and adsorption capacity decrease with increase in the molar ratio of SO/N mixture from 1:1 to 1:9. In the case of ternary mixture of SO, CO, N, having compositions of 0.05, 0.15, 0.8, the selectivity of SO over N is higher than that of CO over N. The maximum selectivity of SO over CO is observed for the COOH functionalized GNR followed by NO and other functionalized GNRs.