丙烯二聚合成4-甲基-1-戊烯反应的热力学研究  

Study on thermodynamics of propylene dimerization to 4-methyl-1-pentene

作　　者：吴建民[1] 孙启文[1] 张宗森[1] 庞利峰[1] 

机构地区：[1]上海兖矿能源科技研发有限公司煤液化及煤化工国家重点实验室,上海201203

出　　处：《天然气化工—C1化学与化工》2014年第2期20-24,共5页Natural Gas Chemical Industry

基　　金：国家重点基础研究发展计划(973计划;2012CB723603)

摘　　要：利用Benson基团贡献法和ABWY法计算了丙烯二聚反应产物的标准生成焓、标准熵和摩尔定压热容,对298K^700K温度下丙烯二聚合成4-甲基-1-戊烯反应体系的反应热、吉布斯自由能以及反应平衡常数进行了详尽的计算,分析了不同反应步骤的热力学平衡与限度,对不同反应发生的热力学可能性与顺序进行了判断,考察了反应温度和压力对丙烯二聚反应化学平衡的影响,计算了特定工艺条件下丙烯二聚各反应的平衡转化率。结果表明:丙烯二聚反应是放热反应,低温时反应均能够自发地进行,且能够进行到较高的程度;从热力学上看,低温、高压有利于丙烯二聚合成4-甲基-1-戊烯反应的进行;除了生成1-己烯外,其它副反应均比生成4-甲基-1-戊烯反应更容易进行;丙烯二聚合成4-甲基-1-戊烯反应适宜的工艺条件为400K^450K,8MPa^15MPa,且在温度428K,压力10MPa下,丙烯二聚各反应的平衡转化率接近于100%。The standard molar enthalpy of formation, standard entropy and isobaric molar heat capacity of propylene dimerization products were estimated by using Benson group contribution method and ABWY method. The enthalpy change, Gibbs free energy change and equilibrium constant of propylene dimerization to 4-methyl-l-pentene reaction system were calculated in detail as a function of the temperature from 298K to 700K. The thermodynamic equilibrium and the limit of different reaction steps were analyzed. The thermodynamic possibility and formation sequences of propylene dimerization reaction system were ＇also judged. The effects of temperature and pressure on the equilibrium conversion were investigated. The equilibrium conversions of propylene dimerization reactions in the specific process condition were obtained according to thermodynamic calculations. The results showed that propylene dimerization is an exothermie reaction, which is spontaneous at low temperature and can reach to a deep extent. Low temperature and high pressure are favored to propylene dimerization to 4-methyl-l-pentene reaction from a thermodynamic point of view. The occurrences of the other side reactions are easier than propylene dimerization to 4-methyl-l-pentene except to 1-hexene. The appropriate process conditions are 400K-450K, 8MPa-15MPa. The equilibrium conversions of all propylene dimerization reactions approach 100% at 428K, 10MPa.

关 键 词：丙烯二聚 4-甲基-1-戊烯 热力学 平衡常数 

分 类 号：TQ221.21[化学工程—有机化工] TQ013.1