Modeling of diffusion and reaction in monolithic catalysts for the methanol-to-propylene process

The present paper gives an insight into the methanol conversion to propylene (MTP) performance in a monolith reactor by means of a two-dimensional adiabatic heterogeneous reactor model accounting for interfacial and intra-particle gradients. Interactions of mass and heat transfer and chemical reactions were taken into account within monolith channels and inside the channel walls. Concentration and temperature profiles in both radial and axial direction were calculated for a multiple-stage monolithic reactor simulating the MTP process with special focus to influence of monolith channel geometries on selectivity of propylene. Calculated results showed that the total yield of light C2–C4 olefins can be achieved high up to 71%, with that of propylene up to 49% by a selected monolith structure of 400 cells per square inch with a 0.2 mm catalytic wall thickness. Thus, the monolithic catalyst with high cell density and thin walls is recommended for the MTP process.

► A multiple-stage adiabatic monolith reactor was simulated.
► The effects of monolith geometries on the performance of MTP process.
► Propylene yield can be significantly improved.
► Hints for monolithic catalyst design were derived.