An efficient titanomaghemite MOF-derived catalyst for reverse water–gas shift

Abstract

In response to the escalating greenhouse gas (GHG) emission crisis, integrating the reverse water–gas shift (RWGS) reaction with Fischer–Tropsch synthesis (FTS) has been identified as a promising two-step approach for converting CO₂ and H₂ into valuable products. However, the requirement for high temperatures to achieve significant CO₂ conversion, along with the formation of undesired products (e.g., methane) at high pressures during the RWGS step, presents challenges for integrating the RWGS reaction with FTS synthesis. In this context, developing a low-temperature RWGS catalyst that can suppress CO₂ methanation, even under high pressure, is paramount for facilitating energy integration between the two processes. In this study, we present an in-depth study of a metal–organic framework (MOF)-derived solid as a catalyst for the low temperature RWGS reaction. Our catalyst showed high activity and stability, achieving up to 97% CO selectivity at close to equilibrium CO₂ conversion levels at moderate temperatures and high pressures. A kinetic study of the resulting titanomaghemite catalyst was conducted to determine the kinetic parameters that describe the catalytic system and to facilitate future reactor and process design.