Numerical study of heat and mass transfer by reverse water-gas shift reaction in catalyst-coated microchannel reactor

Abstract

Reverse water-shift reaction (RWGS) is well known as an endothermic reaction to convert carbon dioxide and hydrogen to carbon monoxide and water vapor at an elevated temperature above 600 °C and also considered as a syngas production process before Fischer-Tropsch (FT) synthesis in generating the synthesis of liquid fuels. Unlike the conventional reactor types, micro-structured reactor has various advantages such as enhanced heat and mass transfer, flow uniformity, higher surface-to-volume ratio, safe processing and easier scale-up. In particular, this paper aims to invesitgate the conversion performance of RWGS reaction in catalyst-coated microchannel reactor whose inside surface is coated with Ni-catalyst by utilizing CFD simulations including chemical kinetics. The analytical model is developed to describe heat and mass transfer with chemical reaction in catalyst-coated microchannel. The effect of channel size, gas velocity, operating temperature, inlet gas composition (molar ratio of H2/CO2) and catalytic area ratio is evaluated by displaying CO2 conversion, temperature distribution, heat transfer, and reaction rate.