Molecular Simulations of Adsorption and Separation of H2S and N2 Mixture by Single Wall Carbon Nanotubes

Adsorption and separation of 1 : 99(volume ratio) H2S/N-2 mixture by single wall carbon nanotubes were studied using the grant canonical Monte Carlo(GCMC) method at a range of nanotube diameters, pressures and temperatures. It is demonstrated that the selectivity towards H2S increases and then decreases with increasing nanotube diameter and the selectivity is highest for (11, 0) carbon nanotube which is due to the synergy of geometry effect and energy effect. It is shown that under different operation conditions, the adsorption isotherm and selectivity can vary significantly. At 100 kPa, the amount of adsorbed of H2S in (11, 0) carbon nanotube and the selectivity towards H2S firstly increase and then decrease with increasing temperatures. Moreover, at 300 K, with increasing pressures, the adsorbed amount of H2S and the selectivity towards H2S decrease. The simulation findings in this work would be helpful for the design and development of sulfur removal processes.