[annu]

hello all,
I am working on catalytic reactor, you can say fixed bed reactor. In this, there are three zones reactant zone, porous zone and product zone. In the porous zone there is catalyst which with time will get deactivated (deposition of coke) because of reaction taking place. Reactants are in gaseous form. problem is i don't understand how to incorporate catalyst. Should i make the mixture of coke and catalyst in materials? In materials, i know the density and other properties but molecular weight of the catalyst is unknown. I am using spalart allmaras model as viscous model. In the species transport, should i activate all of the reaction options, means volumetric, particle surface, wall? i have the kinetics for activation and deactivation, i had made udf for volumetric reaction, where it would be incorporated?

please help me friends i am badly struck, and it is urgent, cuz i am not able to find the answers of my doubts.