正丁烷异构化制异丁烷反应热力学分析及试验研究

在分析正丁烷异构化制异丁烷反应特点的基础上，通过系统的热力学计算，获得了不同反应温度下目标反应的标准摩尔焓变、标准摩尔吉布斯自由能变、标准平衡常数及正丁烷平衡转化率，并以Pt/Al₂O₃-Cl为催化剂进行了正丁烷异构化反应试验研究。结果表明，正丁烷异构化属微放热反应，降低反应温度可提高正丁烷的平衡转化率；对于Pt/Al₂O₃-Cl催化正丁烷异构化反应，反应温度、反应压力、正丁烷进料空速和氢/烃摩尔比均对正丁烷转化率有较明显的影响，选择合适的反应温度和压力，并适当降低进料空速和氢/烃摩尔比，有利于提高正丁烷转化率；在优化的反应条件下，正丁烷的试验转化率与热力学平衡转化率基本吻合，验证了热力学分析结果的可靠性。

THERMODYNAMIC ANALYSIS AND EXPERIMENTAL STUDY ON THE ISOMERIZATION OF n-BUTANE TO ISOBUTANE

Based on the analysis of the reaction characteristic and thermodynamic behaviors of n-butane isomerization to isobutane, standard molar enthalpy change, standard molar Gibbs free energy change, standard equilibrium constant and equilibrium conversion of n-butane at different temperatures were obtained, and the n-butane isomerization over Pt/Al₂O₃-Cl catalyst was investigated. The results show that the isomerization of n-butane is an exothermic reaction, and the equilibrium conversion of n-butane can be increased by lowering the reaction temperature. In the n-butane isomerization catalyzed by Pt/Al₂O₃-Cl, the reaction temperature, reaction pressure, space velocity of n-butane and molar ratio of hydrogen to hydrocarbon (H₂/HC) have obvious effects on the conversion of n-butane. The n-butane conversion can be increased by selecting reaction temperature and pressure carefully and decreasing n-butane space velocity and H₂/HC molar ratio properly. Under optimum reaction conditions, the conversion of n-butane was in good agreement with that of thermodynamic equilibrium, which proved the reliability of thermodynamic analysis.