高等学校化学学报2016，Vol.37Issue(9)：1660-1668,9.DOI:10.7503/cjcu20160337
1-乙胺基-3-甲基咪唑四氟硼酸盐吸收CO2的理论研究
Density Functional Theory Studies on the CO2 Absorption by 1-Ethylamine-3-methylimidazolium Tetrafluoroborate
摘要
Abstract
CO2 absorption mechanism by ionic liquids 1-ethylamine-3-methylimidazolium tetrafluoroborate, which was formulated as [ NH2 e-mim ] [ BF4 ] , was described via density functional theory ( DFT ) . The structure of ionic liquids [ NH2 e-mim ] [ BF4 ] , their reaction intermediates, transition states and products, were optimized using the B3LYP/6-311++G(d, p) basis method, with the optimized configuration parame-ters, vibration frequencies and thermodynamics data obtained. Furthermore, the natural bond orbital atomic charge assignments were also calculated via the natural bond orbital( NBO) method. The computational results demonstrated that the divalent cation [ NH3 e-mim ] 2+, which was produced by the autoprotolysis of cation [ NH2 e-mim]+, could be easily combined with anion [ BF4 ]-, with stronger ionic bond formed. According to the calculation results of standard Gibbs free energy(△G 0—) and enthalpy(△H 0—) , it could be inferred that the absorption of CO2 onto ionic liquids [ NH2 e-mim] [ BF4 ] was step by step, in accordance with the theoreti-cal molar ratio of 2︰1. During the absorption process, the energy barrier of 52. 51 kJ/mol should be overcome for proton transfer reaction.关键词
离子液体/二氧化碳/密度泛函理论/吸收机理Key words
Ionic liquid/CO2/Density functional theory( DFT)/Absorption mechanism分类
化学化工引用本文复制引用
张慧,张红梅,王连军,沈锦优..1-乙胺基-3-甲基咪唑四氟硼酸盐吸收CO2的理论研究[J].高等学校化学学报,2016,37(9):1660-1668,9.基金项目
江苏省高校自然科学研究项目(批准号:12KJB610003)资助. Supported by the Natural Science Research Project of Colleges and Universities in Jiangsu Province, China(No.12KJB610003) （批准号:12KJB610003）
