SO_2催化氧化过程的几个理论问题

Theoretical Discussion on Catalytic Oxidation of Sulphur Dioxide

综合介绍了ＳＯ２催化反应过程中的几个理论问题。认为ＳＯ２在钒催化剂上的液相催化反应可用双钒两段反应机理表征；小颗粒钒催化剂上ＳＯ２的催化反应受液相扩散的影响；钒催化剂的曲节因子在转化率不太高时为４左右，高转化率时曲节因子随转化率增大而明显增大，相应地效率因子下降；低温区钒催化剂活性下降是由于熔盐中析出不溶的无活性的四价钒化合物造成的。并由此提出了考虑多种因素影响的动力学模型。

The theory of catalytic oxidation of SO2 is discussed. The liquid catalytic reaction of SO2 overvanadium catalyst can be expressed by a double vanadium two-step mechanism. The catalytic reaction of SO2 over small vanadium catalyst particles iscontrolled by diffusion in liquid phase. The tortuosity factor for vanadium catalyst is 4 at low conversions, and increases considerably as conversion israised at high conversions while effectiveness factoris decreased. The activity loss in low- temperatureregion is due to the separation of insoluble inactiveV4- compound from molten salt. A dynamical modelincluding various factor consideration is established.