Reverse Water Gas Shift Reaction over High Surface Area γ-Al2O3 Supported Mo2C Nanoparticles Synthesized by Reverse Microemulsion Method

Abstract

Increasing concentrations of greenhouse gases (GHG), especially carbon dioxide (CO2), in the atmosphere are forecasted to result in adverse environmental impacts. One attractive approach for mitigation of CO2 emissions is utilizing this gas for the production of renewable synthetic fuels and chemicals. In particular, the reverse water gas shift (RWGS) reaction converts CO2 to CO, which can further be used to generate valuable chemicals. In this study, MoOx and Mo2C nanoparticles were synthesized by the reverse microemulsion method and analyzed their performance as RWGS catalysts. The catalyst composition, morphology and crystalline structure were investigated by inductively coupled plasma – optical emission spectrometry (ICP-OES), Brunauer-Emmett-Teller (BET) method, X-ray diffraction (XRD), temperature programmed reduction (TPR), transmission electron microscope (TEM) and scanning electron microscope (SEM). The impact of using different preparation method (e.g. reverse microemulsion versus impregnation method) on the catalytic activity, selectivity, and stability were determined using a fixed bed reactor experimental setup. The thermal decomposition processes of the spent catalysts were investigated using thermogravimetric analysis-Fourier Transform Infrared spectroscopy (TGA/FTIR). Overall findings have indicated that Mo2C nanoparticles prepared by the reverse microemulsion method showed higher conversion, 100% selectivity to CO, and significantly more stable performance over extended times on stream than the commercial catalyst, Cu/ZnO/Al2O3 for the RWGS reaction.