Adsorption and molecular simulation of CO2 and CH4 in two-dimensional metal-organic frameworks with the same layered substrate

作者：Li, Libo^*; Yang, Jiangfeng; Li, Junmin; Chen, Yang; Li, Jinping

来源：CrystEngComm, 2013, 15(34): 6782-6789.

DOI：10.1039/c3ce40838h

• COORDINATION POLYMERS
• N-2
• BIOGAS
• GASES
• MOF-5

Cu(1,3-BDC) (1,3-BDC = 1,3-benzenedicarboxylic acid) was found in the interpenetrated metal-organic frameworks [Cu(1,3-BDC)(H2O)]center dot 2H(2)O and Cu(1,3-BDC)(PY)(2). We studied their CO2, CH4, and N-2 adsorption isotherms at high pressure (10 bar) and used density functional theory methods to locate their most stable configurations. We show that [Cu(1,3-BDC)(H2O)]center dot 2H(2)O has a high adsorption selectivity of CO2 over CH4 because of the total lack of CH4 adsorption. Although Cu(1,3-BDC)(PY)(2) has the same layered substrate as [Cu(1,3-BDC)(H2O)]center dot 2H(2)O, except for the insertion of pyridine rings between layers, it adsorbs significantly more CH4, leading to decreased CO2/CH4 adsorption selectivity and increased CH4/N-2 adsorption selectivity. Our experimental and theoretical studies reveal that introducing suitable organic ligands provides more adsorption sites for CH4, while the ligands' occupancy of the spaces between the layers prevents the spread of CO2 molecules.

• 出版日期2013
• 单位太原理工大学