Zn(OAc)2/AC催化固定床上CO2与1,2-丙二醇合成碳酸丙烯酯及其反应机理  

Synthesis of propylene carbonate from CO_2 and 1,2-propylene glycol on fixed-bed reactor and its reaction mechanism catalyzed by Zn(OAc)_2/AC

作　　者：张光洁 耿艳楼[1] 安华良[1] 赵新强[1] 王延吉[1] 

机构地区：[1]河北工业大学化工学院,绿色化工与高效节能河北省重点实验室,天津300130

出　　处：《化工学报》2015年第2期567-575,共9页CIESC Journal

基　　金：国家自然科学基金项目(21076059,21476058,21236001);天津市自然科学基金项目(12JCYBJC12800);河北省应用基础研究计划重点基础研究项目(12965642D)~~

摘　　要：以负载型乙酸锌为催化剂,在固定床上实现了CO2和1,2-丙二醇(PG)合成碳酸丙烯酯(PC)反应。考察了不同载体和负载量对负载型乙酸锌催化性能的影响以及反应条件对PC合成反应的影响。结果表明:负载量为40%(质量分数)的Zn(OAc)2/AC催化性能最好。CO2与PG合成PC适宜的反应条件为:PG、乙腈和CO2的摩尔比为1:1.8:11,CO2压力4.0 MPa,反应温度160℃和液空速0.9 h-1。在此条件下,PC收率和选择性分别为6.3%和49.0%。采用原位红外结合设计实验研究了无水乙酸锌分别与CO2和PG之间的相互作用,发现CO2与乙酸锌之间的化学吸附比较弱,而PG与乙酸锌之间的化学吸附较强,能够活化PG。据此推测了乙酸锌催化CO2与PG合成PC的反应机理。Propylene carbonate（PC） was synthesized on a fixed-bed reactor from CO2 and propylene glycol（PG） catalyzed by supported Zn（OAc）2 catalyst. Then the effect of the kind of carrier and its loading on the catalytic performance and the influence of reaction conditions on PC synthesis reaction were investigated. The results indicates that Zn（OAc）2/AC with loading of 40%（mass） shows better catalytic performance. The suitable reaction conditions are obtained as follows： molar ratio of PG to acetonitrile（solvent） to CO2 is 1：1.8：11, reaction temperature 160℃, CO2 pressure 4.0 MPa and LHSV 0.9 h^-1. Under the above conditions, the yield and selectivity of PC were 6.3% and 49.0%, respectively. The interaction between Zn（OAc）2 and CO2 or PG was investigated by in-situ IR technique combined with some designed experiments. It was found that the chemical adsorption of CO2 on Zn（OAc）2 is weaker while it is much stronger between PG and Zn（OAc）2. Chemical bond between PG and Zn（OAc）2 is found, indicating that Zn（OAc）2 can activate PG in this reaction. Accordingly, the role of Zn（OAc）2 in the catalytic reaction of CO2 and PG to PC is elucidated.

关 键 词：1 2-丙二醇 二氧化碳 碳酸丙烯酯 固定床 催化剂 反应机理 

分 类 号：TQ203.2[化学工程—有机化工] TQ225.5