Effects of physicochemical parameters on the optimized topology of catalyst in micro reactors

Fluid flow, mass transport and catalytic reaction in micro-reactors with catalyst are studied. Optimized structures of the catalyst generating the maximum reaction rate are explored by numerically solving the reactive transport processes combined with topology optimization schemes in COMSOL 5.3a. Effects of several physicochemical parameters including pressure drop, reaction rate constant, permeability of the porous catalyst and radius of the reactor are investigated. Distributions of the optimized structures, velocity, pressure and concentration are discussed in detail. Results show that the four physicochemical parameters have significant effects on the optimized structures of the catalyst obtained, indicating that generally there does not exist a single structure that can result in the maximum averaged reaction rate under different conditions. Three indicators are evaluated, including the averaged reaction rate, conversion ratio and the volume of catalyst. It is found that change trends of different indicators with different physicochemical parameters sometimes are opposite, indicating great challenging for multiple objective optimization.