文献类型：期刊文献

英文题名：Computer simulation for adsorption of CO2, N2 and flue gas in a mimetic MCM-41

作者：Zhuo, Shengchi[1,2]; Huang, Yongmin[1]; Hu, Jun[1]; Liu, Honglai[1]; Hu, Ying[1]; Jiang, Jianwen[2]

机构：[1] Laboratory for Advanced Material, Department of Chemistry, East China University of Science and Technology, Shanghai 200237, China; [2] Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576, Singapore

年份：2008

卷号：112

期号：30

起止页码：11295

外文期刊名：Journal of Physical Chemistry C

收录：EI(收录号：20083411470101)

语种：英文

外文关键词：Surface defects - Flues - Flue gases - Pore size - Silica - Adsorption

摘要：Adsorption of pure and mixed CO2 and N2 is simulated in a mimetic MCM-41. The full-atom MCM-41 model is constructed by caving cylindrical pores from an amorphous silica matrix and energetically optimized. Dreiding force field is used for the dispersive interaction with the atomic charges estimated from the densityfunctional theory calculations. The optimized MCM-41 maintains a hexagonal array of the mesoscopic pores as evidenced by the three characteristic peaks in the XRD pattern. The pore surface of MCM-41 is corrugated and coated with hydroxyls and defects. The pore size exhibits a Gaussian distribution with an average radius of 14.38 ? close to the experimental value. Simulated adsorption isotherms and isosteric heats of CO2 match well with the experimental data. CO2 adsorbs preferentially at the active sites near the pore surface, while N2 tends to adsorb homogeneously on the pore surface. In CO2 and N 2 mixture as a flue gas, CO2 is more adsorbed than N 2. The selectivity of CO2 over N2 drops rapidly with increasing temperature and depends weakly on pressure. At temperatures higher than 400 K, the selectivity approaches a constant and pressure has no discernible effect. ? 2008 American Chemical Society.