Abstract: A new spherical random network model is applied to the problem of diffusion and reaction occurring simultaneously in porous catalysts. The diffusion/reaction equations are solved numerically over the network for the case of a single, isothermal, irreversible first - order reaction. The simulation results show that calculated tortuosities varies with network connectivity as well as the Thiele modulus. This work also suggests that tortuosities obtained under diffusion - only conditions can only be used under the strong reaction control conditions. The simulation results obtained from different network models are carefully analysed and the variation of those are theoretically discussed.

摘要： 提出了一种多孔球形催化剂颗粒随机网络构造方法,并以等温一级不可逆反应为例,对催化剂孔道网络内发生的反应扩散过程进行了模拟计算。模拟结果表明,计算出的曲折因子既是孔网络配位数的函数,又随Thiele模数的变化而不同,在纯扩散条件下测得的有效扩散系数只能应用于扩散影响不严重的反应扩散区域。同时对在不同的网络模型上的模拟结果进行了分析,并对各自得出的结论之间存在的分歧进行了解析。