DRIFTS-MS-SSITKA Study of the Reverse Water-Gas Shift Reaction

Overview & Synopsis

An operando method for the analysis of heterogeneous catalytic reaction was developed using the reactor of a diffuse reflectance FTIR in situ cell and a steady-state isotopic kinetic transient (SSITKA) technique. This method allowed following simultaneously the isotopic exchange of the adsorbates present at the catalyst surface (by DRIFTS) and that of the reaction product (by mass spectrometry). This paper reviews an early example of our studies on the reverse water-gas-shift (WGS, ${\rm CO}_2 + {\rm H}_2 \to {\rm CO} + {\rm H}_2{\rm O}$), also re-emphasising the need to use steady-state conditions if the true operando reactivity of the adsorbates is to be determined.