Question

Accessibility of the surface area of the catalyst is typically non-limiting.

(a) True

(b) False

I had been asked this question in unit test.

The question is from Minimising Mass Transfer Effects in portion Heterogenous Reactions of Bioprocess Engineering

Answer 1

Right answer is (b) False

To elaborate: Rate of catalytic surface reactions is proportional to the catalyst surface area. However, accessibility of that surface area is typically limiting, as most of it is inner surface area inside the porous catalyst structure. Essentially all the surface area of most typical technical catalysts is internal surface area. Hence, a catalyst can only be used at its maximum potential, if diffusion inside the pore structure is not limiting.