Consider the cylindrical porous pellet shown in the figure below. A gas mixture of species A and B continually flows over the top face of the pellet. The sides and bottom of the pellet are sealed, and so serve as an impermeable barrier. Within the porous layer, species A forms species B by A B, with first order rate equation RA k c_A.

a. List at least three relevant assumptions of the mass transfer process, including the likely directions for flux of species A.
b. In the z-direction, what is the differential form of Fick’s Flux Equation?
c. Develop the appropriately simplified General Differential Equation for Mass Transfer, in terms of species A concentration, c_A
d. What are the relevant boundary conditions for the process with respect to species A?

Transcribed Image Text:

flow A+B porous disk with sides and bottom sealed CAO CAO A+B I impermeable r=0 r=R barrier Z=0 -Z=L