尿素醇解制备碳酸丙烯酯的动力学研究  

Kinetic study on preparation of propylene carbonate by alcoholysis of urea

作　　者：吕磊 沈卫华[1] 聂颖颖 焦林郁 方云进[1] LYU Lei;SHEN Wei-hua;NIE Ying-ying;JIAO Lin-yu;FANG Yun-jin(State Key Laboratory of Chemical Engineering,School of Chemical Engineering,East China University of Science&Technology,Shanghai 200237,China;Shaanxi Coal Chemical Industry Technology Research Institute Co.,Ltd.,Xi′an 710070,Shaanxi Province,China;School of Chemical Engineering,Northwest University,Xi′an 710069,Shaanxi Province,China)

机构地区：[1]华东理工大学化工学院化学工程联合国家重点实验室,上海200237 [2]陕西煤业化工技术研究院有限责任公司,陕西西安710070 [3]西北大学化工学院,陕西西安710069

出　　处：《化学工程》2021年第8期51-55,共5页Chemical Engineering(China)

基　　金：陕西省自然科学基础研究计划项目;陕煤联合基金项目(2019JLM-20);国家自然科学基金资助项目(21576083)。

摘　　要：尿素和丙二醇(PG)合成碳酸丙烯酯(PC)反应体系中,使用金属复合氧化物催化剂,常压条件下考察了该催化剂用量、反应时间、温度等因素的影响。经研究得知,该体系在催化剂质量分数为0.7%,170℃加热150 min时,PC最佳收率可达92.1%。将反应过程分解为2部分进行了动力学的研究,首先是尿素和PG酯化成羟丙基氨基甲酸酯(HPC)的过程,之后是HPC环化合成PC的过程。在排除了内外扩散的影响后,设计动力学模型,通过matlab软件拟合后,对方程内各参数进行求解得到尿素、PG和HPC的反应级数分别是0.7,2和0.8,第一、二步反应活化能分别为75.17 kJ/mol和65.24 kJ/mol,指前因子分别为5.3×10^(7)和9.8×10^(7)。显著性检验表明回归效果良好,与测量值吻合。In the synthesis of propylene carbonate(PC)from urea and propylene glycol(PG),using multi-metal oxide as catalysts,the effects of reaction time,temperature and catalyst dosage were studied in the alcoholysis of urea under ambient pressure.The results show that the yield of PC can reach 92.1%under the optimized reaction condition that reaction temperature,reaction time and dosage of catalyst are 170℃,150 min,and 0.7%,respectively.The reaction process was divided into two steps to investigate the kinetics.The first step was the reaction of urea and PG to form hydroxypropyl carbamate(HPC),the second step was to synthesis PC by cyclization of HPC.After excluding the effect of internal and external diffusion,the dynamics model was established and the parameters were calculated by matlab fitting.The reaction order of urea,PG and HPC were 0.7,2 and 0.8,respectively.The activation energy was 75.17 kJ/mol for the first step,and 65.24 kJ/mol for the second step.The pre-exponential factors were 5.3×10^(7) and 9.8×10^(7),respectively.Finally,the test of significance shows the regression effect of the model is good,indicating that the model is consistent with the experiment.

关 键 词：尿素 丙二醇 动力学 碳酸丙烯酯 醇解 

分 类 号：TQ203.2[化学工程—有机化工]