PZ-MDEA 混合胺溶液脱碳的量子化学研究  

Quantum Chemical Study of Decarbonization of PZ-MDEA Mixed Amine Solution

作　　者：王禧雯 樊俊杰[1,2] 毕德贵 席文洁[1] 洪贤康 刘磊 Wang Xiwen;Fan Junjie;Bi Degui;Xi Wenjie;Hong Xiankang;Liu Lei(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China;Shanghai Institute of Non-Carbon-Based Energy Conversion and Utilization,Shanghai 200240,China)

机构地区：[1]上海理工大学环境与建筑学院,上海200093 [2]上海非碳基能源转换与利用研究院,上海200240

出　　处：《燃烧科学与技术》2025年第1期74-80,共7页Journal of Combustion Science and Technology

基　　金：上海高校Ⅳ高峰学科建设项目(ZXWH1450401/008).

摘　　要：基于DFT和过渡态理论,在B3LYP/6-31+G(d)水平上研究了PZ-MDEA混合胺溶液吸收CO_(2)的反应机理,并进行了分子轨道分析.结果表明,在PZ-MDEA混合胺溶液吸收CO_(2)的过程中,PZ直接吸收CO_(2)生成两性离子(PZH+COO-)的反应最容易发生,是CO_(2)捕集的主要反应路径;两性离子可以与PZ、MDEA或H2O发生去质子化反应,其中与MDEA反应的能垒相对最低.通过对比分析发现,两性离子与MDEA反应一方面可以大大降低MDEA质子化反应活化能,另一方面中间产物PZCOO-与PZH^(+)、H_(2)O的反应可以实现PZ的循环,维持CO_(2)的高效吸收.此外分子轨道分析发现PZ-MDEA混合胺的分子轨道能量差值最低(5.95 eV),同样表明PZ对MDEA吸收CO_(2)存在活化作用.Based on DFT and transition state theory,the reaction mechanism of CO_(2) absorption by PZ-MDEA mixed alcohol amine solution was investigated at the B3LYP/6-31+G(d)level,and molecular orbital analysis was performed.The results showed that in the process of CO_(2) absorption by PZ-MDEA mixed alcohol amine solution,the reaction of PZ directly absorbing CO_(2) to generate amphipathic ions(PZH+COO-)was the most likely to occur,which was the main reaction pathway for CO_(2) capture;the amphipathic ions could undergo deprotonation with PZ,MDEA or H2O,with the energy barrier for the reaction with MDEA being the lowest in relative terms.Through comparative analysis,it was found that the reaction of amphoteric ions with MDEA could greatly reduce the activation energy of MDEA protonation reaction on the one hand,and on the other hand the reaction of the intermediate product PZCOO-with PZH^(+)and H_(2)O could realize the recycling of PZ and maintain the efficient ab-sorption of CO_(2).In addition,molecular orbital analysis revealed that the lowest molecular orbital energy differ-ence(5.95eV)was found for the PZ-MDEA mixed amine,which also indicated that PZ had an activating effect on the CO_(2) uptake by MDEA.

关 键 词：CO_(2)吸收 反应机理 混合胺 量子化学 

分 类 号：X701[环境科学与工程—环境工程]