Support acidity as a descriptor for reverse water-gas shift over Mo2C-based catalysts

Abstract Mo2C-based catalysts are highly active and selective for the reverse water-gas shift (RWGS) reaction. By varying the physical and chemical properties of the support, the surface composition of Mo2C, and in turn, RWGS performance can be controlled. Effects of support structure properties are studied via comparison of Al and Si-based amorphous supports (γ-Al2O3 and SiO2) with MFI-type crystalline aluminosilicate zeolites. Support chemical effects are studied via Si/Al ratio and extra framework cation of ZSM-5 (H and Na, Si/Al = 50 and 200). An array of analytical techniques show that structural and chemical characteristics of the support are preserved post-carburization and indicate that support acidity is a key descriptor of Mo oxidation state and RWGS performance.