采用巨正则蒙特卡洛(GCMC)及分子动力学(MD)方法探讨了石墨烯/碳纳米管三维骨架结构(GNHS)对等摩尔CO2/CH4二元混合物的吸附分离性能。模拟结果表明CO2比CH4更易吸附于GNHS中, GNHS与(6,6) SWCNT (单壁碳纳米管)相比具有更高的分离性能。随着温度升高, CO2的吸附量快速降低,而CH4的吸附量则呈现出先升高后降低的趋势。最后采用分子动力学方法计算了CO2与CH4的自扩散系数及停留时间等动力学相关参数,发现CO2在GNHS内扩散的阻力更大。而各组分在吸附剂外部吸附层内的扩散过程对混合物的分离也存在一定影响。%The adsorption and separation behaviors of CO2 and CH4 binary mixture in graphene/nanotube hybrid structures (GNHSs) are investigated by grand canonical Monte Carlo (GCMC) combined with molecular dynamics (MD) simulations. CO2 is preferential y adsorbed in the adsorbents. Compared with a (6, 6) SWCNT (single wal ed carbon nanotube), GNHSs show improved separation performance. As the temperature rises, the loading of CO2 reduces rapidly while the loading of CH4 first increases before being reduced. Final y, the kinetic parameters of CO2 and CH4, such as self-diffusivity and residence time, are calculated by MD simulation. The CO2 molecules diffusing in the GNHS need to overcome a higher barrier relative to that for CH4. The diffusion of the two components in the adsorption layer outside of adsorbent also influences the separation of the mixture.
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