Selectivity of new siliceous zeolites for separation of methane and carbon dioxide by Monte Carlo simulation

The adsorption and separation properties of new siliceous zeolites (such as STW, SOF, PUN, STO, SSF, RWY, LTF, IWS, ITR, SVR, BSV and SFS) were investigated by grand canonical Monte Carlo (GCMC) simulation. The force fields of COMPASS, PCFF, CVFF, DREIDING and Universal were used in the GCMC simulation to select the appropriate force field for obtaining the adsorption isotherms of methane and carbon dioxide on the purely siliceous zeolites. The simulation results by PCFF force field show a good agreement compared to the experimental data available. The adsorption isotherm of pure and binary mixtures of methane and carbon dioxide on 12 new zeolites were calculated. In addition, the effects of pressure and bulk gas composition on the selectivity of carbon dioxide/methane were examined. The results demonstrate that RWY zeolite is a good candidate for the adsorption of methane and carbon dioxide at high pressure and the adsorption of methane and carbon dioxide (mol/kg zeolite) in RWY zeolite are 6.86 and 8.79 mol/kg, respectively. Also RWY zeolite is the best zeolite types for the maximum separation of binary mixture of methane and carbon dioxide. (C) 2013 Elsevier Inc. All rights reserved.