Elements of Chemical Reaction Engineering, 5th Edition

15. Diffusion and Reaction

Research is to see what everybody else sees, and to think what nobody else has thought.

—Albert Szent-Gyorgyi

Overview. In this chapter we will develop models for diffusion with reaction in single-phase and two-phase systems. We start off with a discussion of diffusion and reaction in catalyst pellets. In Chapter 10, we assumed each point on the interior of the catalyst pellet’s surface was accessible to the same concentration. However, when the reactants must diffuse inside the catalyst pellet’s in order to react, we know the concentration at the pore mouth must be higher than that inside the pore. Consequently, the entire catalytic surface is not accessible to the same concentration; therefore, the rate of reaction ...