Adsorption Properties Of Ordered Mesoporous Carbon Material CMK-3 Studied By Molecular Simulation

Because of the aggravation of energy consumption and greenhouse effect, more and more researchers from various countries accelerate to develop the storage technology about CH4,H2 and CO2. Compared with compression and liquefied technology, adsorption technology is more effective and useful, when it comes to safety, cost and efficiency of energy. Therefore, the development of porous materials has become one of most popular areas due to their extensive applications in gas storage and separation. Ryoo has produced the order mesoporous carbon material CMK-3, which was produced by the template technology, the caron souce was cane sugar and SB A-15 is the template. The material CMK-3 has the properties of order pores, narrow pore size distribution, continuous adjustable pore size and bigger surface area. So it is hopeful to be utilized at aspects of adsorption,separation and catalysis.We use the grand canonical monte carlo simulation(GCMC) to study the adsorption property of CH4,N2 and CO2 in CNK-3 material. Based on dual-site Langmuir-Freundlich(DSLF) model, ideal adsorption solution theory(LAST) was utilized to predict the adsorption separation of binary mixtures.In this study, we use the grand canonical monte carlo simulation(GCMC) to study the adsorption property of pure gases in CMK-3 which is from Tianjin university ZHOU's paper. GCMC simulations show that with a maximum excess uptake of 10 and 15mmol/g, the optimum temperature and pressure is obtained at 208K, 4MPa and 298K,6MPa for pure CH4 and CO2 adsorption, respectively. Basing on the existing model parameters, the structural parameters were optimized. The result show that with a maximum excess uptake of CH4 was 9.6mmol/g at 298K, the optimum structural parameters a=6nm and w=3nm when the pressure was 15MPa; with a maximum excess uptake of CO2 was 20.76mmol/g at 298k, the optimum structural parameters a=6nm and w=2.5nm when the pressure was 5MPa. Based on dual-site Langmuir-Freundlich (DSLF) model, ideal adsorption solution theory (IAST) was utilized to predict the adsorption separation of binary mixtures. The adsorption selectivity of SCO2/CH4 is approximate to that of SCH4/N2, with a value about 3 at 298 K and 4 MPa, while N2-CO2 system has a greatest CO2 selectivity, reaching 7.5 at the same condition. It indicates that CMK-3 material is a promising candidate for natural gas separation.