化工进展2023，Vol.42Issue(11)：6015-6030,16.DOI:10.16085/j.issn.1000-6613.2022-2319
多元胺-TFSA型质子化离子液体吸收CO2的理论分析
Theoretical analysis of CO2 absorption by polyamines-TFSA type protic ionic liquids
摘要
Abstract
Three protic ionic liquids(PILs)composed of the same anion of[TFSA＝(CF3SO2)2N-]and different cations of N-hexylammonium(HHexam+),monoprotic hexylethylenediaminium(Hhexen+)and hexyldiethylenetriaminium(Hhexdien+),[HHexam][TFSA],[Hhexen][TFSA],and[Hhexdien][TFSA]were studied for the absorption of CO2.First,the more stable configurations of the three PILs were optimized via the M06-2X/6-311G(d,p)of the density functional theory.The results indicated that the stronger N—H···N-type hydrogen bonds were formed mainly between the N-atoms in the cations and the N-atoms in the anion of the PILs.Then,the configurations of PIL-Nco2 were optimized.The N—H···O-type weak-or moderate-strength hydrogen bonds were formed mainly between the N—H bond in the cation of the PIL and the O atoms of CO2.The results of the vibrational frequency of the N—H bond,and the electron density and the second-order perturbation energy of N—H···O showed that a single molecule of[HHexam][TFSA],[Hhexen][TFSA]and[Hhexdien][TFSA]was saturated when bonded with 2,3 and 4 CO2 molecules,respectively.Meanwhile,the results calculated by COSMOtherm software found that the Henry constants(kPa)for CO2 in the three PILs varied as 1.91×104 for[HHexam][TFSA]>1.68×104 for[Hhexen][TFSA]>1.51×104 for[Hhexdien][TFSA],indicating that the solubility of CO2 in the PILs followed the order of[Hhexdien][TFSA]with three amino groups in the polar head>[Hhexen][TFSA]with two amino groups>[HHexam][TFSA]with one amino group.These results suggested that the number of amino groups in the PIL structure had a significant effect on its ability to absorb CO2.With increasing number of amino groups in the structure of PILs,its solubilization capacity for CO2 increased.关键词
多元胺型质子化离子液体/二氧化碳/分子间氢键作用/密度泛函理论/分子中原子理论Key words
protic ionic liquids with polyamines/carbon dioxide/intermolecular hydrogen bonding/density functional theory(DFT)/atoms in molecules(AIM)分类
化学化工引用本文复制引用
米泽豪,花儿..多元胺-TFSA型质子化离子液体吸收CO2的理论分析[J].化工进展,2023,42(11):6015-6030,16.基金项目
宁夏高等学校研究项目(NGY2020063). （NGY2020063）
