The processes involved in the separation of gaseous CH4/CO2 mixtures using a nanoporous graphene membrane were simulated using a molecular dynamics method, and the effects of three functional modifications (i.e., N/H, al H, and N/―CH3 modifications) in the nanopores were analyzed. The results showed that the gas molecules could form an adsorption layer on the surface of the graphene. The adsorption intensity of the CO2 molecules was higher than that of the CH4 molecules. The functional modifications in the nanopores not only reduced the permeable area, but also improved the adsorption intensity of the gas molecules by changing the potential distribution of atoms at the edge of nanopores, and therefore affecting the permeability and selectivity of the gas mixture being separated by the nanoporous graphene membranes. Furthermore, the permeability of the CO2 molecules was as high as 106 GPU (1 GPU=3.35×10-10 mol∙s-1∙m-2∙Pa-1), which was far greater than those of the existing polymer gas separation membranes. These results therefore demonstrate that nanoporous graphene membranes could be used in an extensive range of applications in industrial gas separation processes, such as natural gas processing and CO2 capture.%采用分子动力学方法模拟CH4/CO2混合气体在多孔石墨烯分离膜中的分离过程，分析了3种纳米孔功能化修饰(N/H修饰、全H修饰和N/―CH3修饰)对分离过程的影响规律.模拟结果表明气体分子会在石墨烯表面形成吸附层， CO2分子的吸附强度高于CH4分子.纳米孔的功能化修饰不仅减小了纳米孔的可渗透面积，还通过影响纳米孔边缘原子的电荷分布提高了气体分子的吸附强度，进而影响了混合气体分子在多孔石墨烯分离膜中的渗透性和选择性. CO2分子在多孔石墨烯中的渗透率能达到106 GPU (1 GPU=3.35×10-10 mol∙s-1∙m-2∙Pa-1)，远远高于传统的聚合物分离膜.研究表明多孔石墨烯分离膜在天然气处理、CO2捕获等工业气体分离过程中具有广泛的应用前景.
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