ABSTRACT
This chapter considers optimization of the catalyst distribution in a single pellet; It discusses the same problem is considered in the context of a fixed-bed reactor. The chapter also discusses the optimization of catalyst distribution in the presence of deactivation processes. It also discusses the preparation of pellets with nonuniform distribution of the catalyst. A great deal of effort has also been invested in the preparation of nonuniformly active catalysts. The dynamic behavior of pellets with Dirac and step distributions where Langmuir–Hinshelwood type of reaction occurs was analyzed by Brunovska. It was found that for Dirac catalysts, depending on the value of Thiele modulus, moving the location of the catalyst toward the pellet center can lead to periodic oscillations. The underlying reason for improved performance of Dirac catalysts, as demonstrated in previous sections, is appropriate manipulation of concentration gradients that develop within the pellet.
