An experimental and simulation study of binary adsorption in metal-organic frameworks

Available online 31 March 2015Abstract Large surface area, high gas adsorption capacity and convenient synthesis methods make microporous metal-organic frameworks (MOFs) a promising adsorbent for gas separation of CO2/N2 and CO2/CH4. This study examines the selective adsorption of CO2 on MOFs through the experimental measurement of equilibrium adsorption capacities from pure fluids (CO2, CH4 and N2) and mixtures of CO2/N2 and CO2/CH4. The derived adsorption selectivity from binary adsorption measurements is higher than the ideal selectivity. Comparing with direct binary adsorption experiments, the Ideal Adsorbed Solution Theory (IAST) model using best-fit parameters for Langmuir isotherms of each pure fluid provides satisfactory predictions for the binary mixtures of CO2/N2 and CO2/CH4. This combined experimental and modeling approach can provide criteria to screen metal-organic frameworks for the separation of gas mixtures at industrially relevant compositions, temperatures and pressures.Ying Yang, Chatcharin Sitprasert, Thomas E. Rufford, Lei Ge, Pradeep Shukla, Shaobin Wang, Victor Rudolph, Zhonghua Zh