采用巨正则系综的蒙特卡罗法，利用几种通用力场对LTA型4A分子筛吸附CO2进行模拟研究，基于Dreiding力场分析力场参数σ和ε对模拟结果的影响，得到适用于4A分子筛吸附CO2的准确Dreiding力场参数。将该力场参数应用到LTA型5A分子筛吸附模拟中，得到5A分子筛吸附模拟的力场参数。最后将4A分子筛吸附CO2的力场参数应用到FAU型13X分子筛的吸附模拟中。结果表明：模拟结果与实验数据吻合较好，分子筛阳离子的改变对吸附力场影响较大，而分子筛结构对力场的影响相对较小。与13X具有同种阳离子的4A分子筛力场参数可直接作为13X分子筛的力场，具有通用性。%Adsorptions of CO2 in 4A zeolites of LTA was investigated by grand canonical Monte Carlo (GCMC) method. The influences of σ and εparameters in Dreiding force field on the simulation results were analyzed by GCMC method. The opti-mized force fields were obtained by fitting the experimental data of 4A zeolites of LTA. Then the CO2 adsorption isotherm on 5A zeolites of LTA was computed based on the obtained force fields. According to the influences of σ and ε parameters in Dreiding force field on the simulation results, the suitable force field parameters of CO2 adsorption on 5A zeolites were quick-ly obtained. Finally, CO2 adsorption isotherm on 13X zeolites of FAU was computed by the optimized force field parameters. The results show that the simulated results are in a good agreement with the experimental data. The change of cation in mo-lecular sieve has a greater influence on the adsorption force field than the molecular sieve structure, the optimized force field parameters which describe the 4A zeolites of LTA well, are suitable for the CO2 adsorption on 13X zeolites of FAU. The con-clusions are versatility.
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