DIFFUSION, CONVECTION, AND REACTION IN CATALYST PARTICLES - ANALOGY BETWEEN SLAB AND SPHERE GEOMETRIES

Expressions for the calculation of the ''augmented' intraparticle effe ctive diffusivity have been obtained for diffusion, convection, and re action problems in catalyst particles with slab and sphere geometry at steady state and in the transient regime. Analytical solutions for th e time domain model equations for both geometries have been derived, a nd a numerical scheme for solving the spherical particle model equatio ns is also presented. An equivalence ratio, l/R, between the slab and the sphere characteristic dimensions has been obtained from these resu lts for steady-state and transient operation. Finally, a comparison of the actual use of the sphere and the slab model equations is presente d.