EFFECTIVENESS OF BIDISPERSE CATALYSTS WITH CONVECTIVE FLOW IN THE MACROPORES

Effectiveness factors of bidisperse catalysts for first-order irreversible reaction and diffusion in the microspheres and diffusion and convection in the macropores are calculated for slab and sphere pellet geometries. The model parameters are the ratio of diffusion time constants in macropores and microspheres alpha, the intrapellet convection number lambda, the fraction of active sites at the surface of microspheres gamma, and the Thiele modulus for the microspheres phi(mi). The influence on the catalyst performance of convective flow in the macropores is addressed.