Separation-Based Adsorption of H2 from Binary Mixtures inside Single, Double, Triple Walled Boron-Nitride Nanotubes: A Grand-Canonical Monte-Carlo Study

This study investigates the separation based on adsorption of the binary gas mixture of hydrogen with biogas (gases: CO2, CH4, O-2, N-2) and inert gases (gases: He, Ne, and Ar) using single-walled ((7,7), (15,15), (29,29), (44,44), (58,58) and (73,73) SWBNNTs), double-walled ((11,11)@(15,15), (7,7)@(22,22) DWB-NNTs) and triple walled ((8,8)@(11,11)@(15,15) and (7,7)@(15,15)@(22,22) TWBNNTs) boron nitride nanotubes via the grand canonical Monte Carlo (GCMC) simulation. Two models, namely, spherical and site-site models, are employed for gas. Two conditions are used for the SWBNNTs, i.e., SWBNNTs with atomic charges and SWBNNTs without atomic charges. This paper also examines the impact of nanotube diameters on binary mixture adsorption. The results indicate that considering the H-2/gas separation in the studied BNNTs, the H-2 separation from He and the H-2 separation from Ar have the maximum and minimum selectivity values, respectively. Also, with increasing pressure and temperature, the values of the H-2/He selectivity in the studied BNNTs decrease.