以石墨片微元构建的多孔碳材料作为活性炭的结构模型，采用巨正则蒙特卡罗方法(GCMC)和分子动力学方法(MD)，从分子层面研究甲烷和甲苯在活性炭中的吸附和扩散特性. 结果表明，石墨片微元大小对多孔碳材料吸附甲烷和甲苯有一定影响，37个碳环构成的多孔碳材料是最佳的吸附结构；甲烷气体在活性炭材料中扩散较快，甲苯在活性炭中扩散较慢，随碳环碳原子数增加，气体在多孔碳材料中的自扩散系数逐渐增大；引入基团会使最优密度向高密度方向偏移，用不同基团表面改性的吸附量顺序为羟基>氨基>羧基>未改性，基团引入会改善材料的孔结构，有利于吸附量的增加.
The porous carbon material constructed with graphite slice was used as the structure model of activated carbon. Grand Canonical Monte Carlo (GCMC) and molecular dynamics (MD) methods were used to study the adsorption and diffusion characteristics of methane and toluene in activated carbon at the molecular level. The results showed that the small element size of graphite sheet had certain influence on the adsorption of methane and toluene on porous carbon materials, and the porous carbon material composed of 37 carbon rings was the best adsorption structure. The diffusion rate of methane in the activated carbon material was faster, and the diffusion rate of toluene in the activated carbon was slower. With the increase of carbon atoms in the carbon ring, the self-diffusion coefficient of the gas in porous carbon increased gradually. The group made the optimal density shift to the high density after surface modification. The adsorption capacity was list as the order of hydroxyl>amino>carboxyl>none modified. The introduction of groups to improve the material pore structure helped to increase the adsorption capacity. The adsorption and diffusion characteristics of activated carbon to methane and toluene gases were studied, and the microcosmic mechanism of adsorption and diffusion of activated carbon was analyzed, providing ideas and guidance for the selection and development of excellent adsorption materials.
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