Kinetics of reverse water‐gas shift reaction over Pt/Al2O3 catalyst

Abstract

AbstractThe CAMERE (Carbon Dioxide Hydrogenation to Form Methanol via a Reverse Water‐Gas Shift Reaction) process for the transformation of CO2 into methanol comprises reverse water‐gas shift (RWGS) and methanol production. In this work, the reaction kinetics of RWGS was investigated using a commercial Pt/Al2O3 catalyst. Catalytic runs were accomplished in a fixed‐bed flow reactor at 0.1 MPa in the 573–873 K range. The space time was varied in the 0.03–0.25 g · h/L range. The prevalence of the chemical control regime was established. The influence of reaction variables on the catalyst performance was investigated, and it was found that the increase in pressure resulted in a growing CO2 conversion value. The reactor was operated under differential reaction conditions and the influence of the H2/CO2 ratio in the feed on reaction rates was studied. Finally, the reaction pathway was analyzed using the associative and redox reaction mechanisms, and the latter appeared dominant over Pt/Al2O3.