烷烃二氧化碳氧化脱氢的反应平衡和热匹配工艺分析

Thermodynamic analysis of dehydrogenation of alkanes with CO_2 and its thermal matching with catalytic exothermic reactions

对乙烷、丙烷和乙苯的二氧化碳氧化脱氢反应进行了热力学分析,计算表明:三个体系平衡转化率的变化规律上大致相同,都随温度升高而升高,随压强增大而减小,随进料中CO2浓度增大而增大,进料中水蒸气浓度对平衡转化率影响不大。另外,利用所得结果讨论了利用结构化催化剂将脱氢反应和甲烷催化燃烧反应的吸、放热耦合工艺中的热匹配和物料匹配问题。

Thermodynamic analysis of dehydrogenation of ethane, propane and ethylbenzene with CO2 were made, including equilibrium conversions and thermal effects of the reaction, and its thermal matching with catalytic exothermic reactions. Effects of the reaction conditions on the equilibrium conversion were studied. The results show that these three systems are almost the same, i.e., the equilibrium conversion rates increase with increase in temperature, decrease in pressure and increase in ratio of C02 in reaction gas, but the ratio of the vapor hardly affects the equilibrium conversion rates. Besides, a new process in which dehydrogenation reactions are coupled with the catalytic combustion reaction of methane by the monolith catalysts is also discussed in terms of the thermal matching and material matching conditions between the two types of reactions.