硫化氢在金属-有机骨架材料中吸附与分离的计算模拟
Computational Simulation of Adsorption and Separation for Hydrogen Sulfide in Metal-Organic Frameworks

摘 要: 采用优化的DREIDING力场参数，通过巨正则系综蒙特卡洛(GCMC)模拟方法对天然气中的两种气体CH4和H2S在Cu6(BTTC)4(H2O)6？xS (1)和[(CH3)2NH2]3[(Cu4Cl)3(BTTC)8]？yS (2)两种金属有机骨架(MOFs)材料中的吸附与分离性能进行了比较研究.结果证明了聚合物2的吸附量和分离性能相比之下高于聚合物1，且两种材料的吸附机理存在差异，聚合物1中金属Cu和有机基团对于吸附两种气体没有明显的作用，主要分布在小孔道和大孔道；然而聚合物2中H2S和CH4主要吸附在有机基团、金属Cu和-Cl基团周围.则含有-Cl基团的聚合物2展现了优越的吸附能力和稳定性.总而言之，本文获得的结果可以应用于此类研究领域，因此在环境范围中吸附去除污染物可以产生更深层次定性和定量的作用.
Abstract: The adsorption and separation properties of CH4 and H2S molecules in two metal-organic frameworks (MOFs) including Cu6(BTTC)4(H2O)6？xS(1) and [(CH3)2NH2]3[(Cu4Cl)3(BTTC)8]？yS(2) were studied using the grand canonical Monte Carlo (GCMC) simulation method with the optimized parameters obtained using the DREIDING force field. The results show that adsorption and separation properties of complex 2 are higher than those of complex 1, and there are differences of adsorption mechanisms between the two materials. Adsorption of CH4 and H2S have no obvious effects for complex 1, in which possess metal Cu and organic groups, mainly distribute in small channel and big channel; However for complex 2, adsorption of H2S and CH4are mainly on the side of organic linkers, metal Cu and -Cl group. The complex 2 that have the ？CCl groupshows great superiority of adsorption capacity and stability for CH4 and H2S. Overall, the results obtained in this work could be routinely applied to different case studies, thus yielding deeper qualitative and quantitative insights into adsorption pollutant removal processes in environmental fields.