二齿螯合催化剂铑甘氨酸的分子设计及催化羰基化反应性能研究  

Molecular Design of Rhodium Glycine Catalyzed by Bidentate Chelation and Study the Catalytic Performance of Carbonylation Reaction

作　　者：兰丽萍 叶家俊 高雄 刘莉娟 吉文欣[1] Lan Liping;Ye Jiajun;Gao Xiong;Liu Lijuan;Ji Wenxin(State Key Laboratory of High-effi ciency Utilization of Coal and Green Chemical Engineering,College of Chemistry and Chemical Engineering,Ningxia University,Ningxia,750021)

机构地区：[1]宁夏大学化学化工学院省部共建煤炭高效利用与绿色化工国家重点实验室,宁夏750021

出　　处：《当代化工研究》2022年第14期21-23,共3页Modern Chemical Research

基　　金：宁夏重点研发计划东西合作项目“煤气化渣处理及资源化关键技术研究与应用”(项目编号:2019BFH02014)。

摘　　要：针对工业铑碘催化剂的稳定性问题,采用分子设计方法得到铑甘氨酸催化剂,通过理论计算得到催化反应的机理及各基元反应的中间体、过渡态以及产物的几何结构,并对各个驻点能量进行了零点能校正(Zero-point energy),结果表明,铑甘氨酸催化剂具有双齿五元环螯合结构,给电子基团的甘氨酸配体使Rh更具富电子性,不对称的配位结构利于决速步骤能垒的降低,双齿螯合结构利用空间位阻效应,有效防止Rh形成二聚体而沉淀失活,从而提高催化剂稳定性。在190℃、2.5MPa、水含量6wt%以及溶剂醋酸含量达到54wt%时,铑甘氨酸催化剂催化以甲醇为原料的羰基化反应醋酸选择性达到100%,甲醇的转化率高于99%,醋酸收率达到99.83%。Catalyst molecular design is an important way to achieve high-efficiency catalytic reactions.In this study,we have designed a glycine ligand through the theoretical study of the catalytic reaction,and then synthesized rhodium glycine catalyst of methanol carbonylation.The research found that after Rh-glycine replaced I of the industrial RhI catalyst,the Rh-glycine catalyst with a five-membered ring chelating structure was formed.The rate-determining step of the catalytic reaction has lower reaction barrier and higher activity.Due to the steric hindrance of the bidentate chelate structure,the catalyst is difficult to polymerize and has higher stability.The catalyst performance evaluation indicates that the catalyst exhibited superior catalytic performance on 2.5 MPa,190℃,6wt%water and 54 wt%acetic acid,the selectivity of acetic acid was 100%,The conversion of methanol is higher than 99%,and the yield of acetic acid is 99.83%.

关 键 词：羰基化 醋酸 甘氨酸 铑基催化剂 

分 类 号：O643[理学—物理化学]