孔扩散阻力对多孔催化剂失活动力学的影响(英文)

Effect of Pore Diffusion Resistance on the Deactivation Kinetics of Porous Catalyst

目前,在强扩散区城中,失活催化反应的分离型动力学方程式仅能用于1级反应和1级独立失活系统。本文把此类方程式扩展应用于各种1,2级反应和1,2级独立失活系统,同时针对气-固相反应器中气相流动呈活塞流或全混流的情况,讨论了如何由实验求取有关的动力学速率常数值。研究结果表明,过程存在孔扩散阻力时,反应转化率随着反应时间降低的速率比无孔扩散阻力的情况要慢。此外,对浓度独立失活和分离型动力学方程的特征也作了论述。

To date, the separable performance equations for deactivating catalytic reactions in the strong pore diffusion resistance regime have only been solved for first order reaction and first order independent deactivation. Here we extend that analysis to all combinations of reactant-controlling first and second order reaction with first and second order independent deactivation. We then show how to evaluate the pertinent rate constants from experiments in reactors with either plug flow of gas (packed bed reactors) or mixed flow of gas (recirculating, Carberry, or Berty type reactors). The results of studies show that in the diffusion influenced regime, the conversion decreases with time more slowly than in the diffusion free regime. Besides, the characteristics of concentration-independent deactivation and separable kinetic rate form have also been discussed.