Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China.
J Environ Sci (China). 2020 May;91:271-278. doi: 10.1016/j.jes.2020.01.019. Epub 2020 Feb 5.
Various computational methods were employed to investigate the zwitterion formation, a critical step for the reaction of monoethanolamine with CO, in five solvents (water, monoethanolamine, propylamine, methanol and chloroform) to probe the effect of hydrogen bond capacity of solvents on the reaction of amine with CO occurring in the amine-based CO capture process. The results indicate that the zwitterion can be formed in all considered solvents except chloroform. For two pairs of solvents (methanol and monoethanolamine, propylamine and chloroform) with similar dielectric constant but different hydrogen bond capacity, the solvents with higher hydrogen bond capacity (monoethanolamine and propylamine) facilitate the zwitterion formation. More importantly, kinetics parameters such as activation free energy for the zwitterion formation are more relevant to the hydrogen bond capacity than to dielectric constant of the considered solvents, clarifying the hydrogen bond capacity could be more important than dielectric constant in determining the kinetics of monoethanolamine with CO.
采用多种计算方法研究了一乙醇胺与 CO 反应的两性离子形成这一关键步骤，该反应在五种溶剂（水、一乙醇胺、丙胺、甲醇和氯仿）中进行，以探究溶剂氢键能力对胺基 CO 捕获过程中胺与 CO 反应的影响。结果表明，除氯仿外，两性离子均可在所有考虑的溶剂中形成。对于介电常数相似但氢键能力不同的两对溶剂（甲醇和一乙醇胺、丙胺和氯仿），氢键能力较高的溶剂（一乙醇胺和丙胺）有利于两性离子的形成。更重要的是，两性离子形成的动力学参数，如形成自由能，与考虑溶剂的氢键能力比介电常数更相关，这阐明了在确定一乙醇胺与 CO 的反应动力学时，氢键能力可能比介电常数更重要。
