异丁烷正构化反应的热力学分析

The thermodynamic analysis of the isobutane normalization reaction

对异丁烷的正构化过程进行热力学分析,重点计算异丁烷正构化过程中各反应的标准摩尔反应焓、标准摩尔反应吉布斯自由能和标准平衡常数,分析各种反应的竞争趋势以及温度、氢烃比对反应平衡转化率的影响。结果表明,异丁烷正构化与异丁烷裂解反应都属于吸热反应,标准平衡常数随着温度的升高而增大,较高的反应温度对这两个反应均有利。在热力学上,高温有利于异丁烷正构化反应的进行,随着反应温度的升高,异丁烷的平衡转化率增大。异丁烷裂解以生成甲烷和丙烯为主,且异丁烷裂解反应比异丁烷正构化反应更容易进行。氢烃比对异丁烷正构化反应的转化率和选择性有重要影响,应综合考虑异丁烷的脱氢过程和正丁烯的加氢过程,选择适宜的氢烃比。

The thermodynamic analysis was performed on the isobutene normalization,and the standard molar enthalpy of reaction,standard molar reaction Gibbes free energy and standard balance constant were calculated.The competitive trends of various reactions and the effects of temperature,hydrogen and hydrocarbon ratio on equilibrium conversion were analyzed.Results showed that the reactions of the isobutene normalization and the cracking reactions belonged to the heat absorption reaction.The standard balance constant increased as the temperature increased,and the higher reaction temperature benefit to these two reactions.In terms of thermodynamics,cracking reactions were easier to perform more than the isobutene normalization reactions.Higher temperatures were conducive to the development of a positive normalization reaction.The balance conversion rate of isobutane increased with the growth of the reaction temperature.The hydrogen-to-oil ratio has an important influence on the conversion rate and selectivity of isobutane normalization reaction.When choosing a hydrocarbon ratio,the dehydrogenation process of isobutane and the hydrogenation process of the n-butene should be considered,and the appropriate hydrocarbon ratio should be selected.