裂解汽油中噻吩加氢脱硫反应宏观动力学

Global Kinetics of Thiophene Hydrodesulfurization in Pyrolysis Gasoline

采用微型等温积分反应器,以组分苯、苯乙烯、噻吩与溶剂正己烷的混合物作为模型化合物,在消除催化剂外扩散影响的基础上,建立了幂函数型的噻吩加氢脱硫反应宏观动力学模型并研究裂解汽油二段加氢过程中噻吩在 Co-Mo/Al_2O_3催化剂上的加氢脱硫反应动力学。通过对比研究噻吩在单一体系和模型化合物中的加氢脱硫反应,探讨了裂解汽油中不饱和烃对噻吩加氢脱硫的影响。实验结果表明,裂解汽油中的不饱和烃会影响噻吩加氢脱硫反应速率,但并不改变其反应机理。噻吩转化率的模型计算值与实验值吻合较好,说明所建立的动力学模型适合描述裂解汽油二段加氢过程中噻吩的加氢脱硫反应。

The global kinetic model with power-law type was proposed for thiophene hydrodesulfurization at the second stage hydrogenation of pyrolysis gasoline （pygas） over Co-Mo/Al2O3 with the model pygas composed of benzene, styrene, thiophene and n-hexane. Experiments were conducted in an integral micro-reactor after eliminating the effect of external diffusion. By comparison of thiophene hydrodesulfurization between the simple system with thiophene and n-hexane and the model pygas, the influence of unsaturated hydrocarbons in the model pygas was explored. The results showed that the unsaturated hydrocarbons had effects on thiophene hydrodesulfurization velocity, but not altered thiophene hydrodesulfurization mechanism. The calculated values of thiophene conversion agreed with the experimental values well and the power-law type global kinetic model was suitable to describe the thiophene hydrodesulfurization at the second stage hydrogenation of pyrolysis gasoline.