Binary Adsorption Equilibrium of CH4, N2 and CO2 on Zeolite ZSM-5

Adsorption equilibrium isotherms of CH4, N2 and CO2 on zeolite ZSM-5 were measured by Rubotherm magnetic suspension balance in the pressure range of 0-500 kPa and the temperatures range of 273-353 K. Sips model, Toth model and MSL model were used to fit the experimental data with an acceptable accuracy, and the model parameters were obtained by the non-linear regression method. Binary adsorption isotherms of CO2/N2, CO2/CH4 and CH4/N2 were measured by the magnetic suspension balance with the different compositions in the pressure range of 0-500 kPa at 293 K. The Sips model-based ideal adsorbed solution theory (IAST) and two-component MSL model were used to simulate the competitive adsorption equilibrium isotherms of CO2/N2, CO2/CH4 and CH4/N2. Furthermore, the selectivity of CO2/N2, CO2/CH4 and CH4/N2 gas mixtures were calculated, and the feasibility of adsorption separation, using zeolite ZSM-5 as adsorbent to separate CO2 from flue gases (CO2/N2), CH4 from landfill gases (CO2/CH4) and coal mine gases (CH4/N2) was evaluated.