ABSTRACT
This chapter discusses the state of several classes of single-pellet multiphase reaction-transport models. The impact of partial external wetting on overall rate has been indirectly estimated in lab-scale trickle-bed reactors. The process of rate enhancement by partial external wetting during a volatile reactant limited reaction in a cocurrent downflow trickle-bed reactor can be exploited by periodic operation. The chapter also discusses the key aspects of modeling exothermic reaction with phase transition in the multiphase fixed-bed reactor. The increasing use of multiphase catalytic reactions in the processing of chemicals demands an improved understanding of the local reaction-transport interactions in the multiphase reactor. The trickle-bed reactor can operate in several flow modes, including co-current downflow, cocurrent upflow, or countercurrent flow. While surface flux continuity holds everywhere, differences in transport rates on the actively or inactively wetted and nonwetted surface implies spatially nonuniform surface conditions.
