Molecular simulation of biogas sweetening by the MIL-47 nanostructure

Absorption and separation of carbon dioxide and hydrogen sulfide from biogas by the metal organic framework MIL-47 have been investigated by using the Monte Carlo method. The simulation results have a good agreement with the available experimental data. At first, the adsorption isotherm of pure, binary and ternary blend of methane, carbon dioxide, and hydrogen sulfide gases were studied. The simulation results show that the gas adsorption increases by decreasing and increasing in the temperature and pressure, respectively, and the pure absorption of hydrogen sulfide gas in the MIL-47 is higher than the other gases. The selectivity of carbon dioxide and hydrous sulfide relative to methane gas calculates 0.2 and 2.9 at ambient temperature and pressure, respectively. Therefore, the metal organic framework MIL-47 is not suitable for the absorption and separation of carbon dioxide gas, but it is good able to separation of hydrogen sulfide from biogas.