Supported Nanostructured Mo(x)C Materials for the Catalytic Reduction of CO(2) through the Reverse Water Gas Shift Reaction

Mo(x)C-based catalysts supported on γ-Al(2)O(3), SiO(2) and TiO(2) were prepared, characterized and studied in the reverse water gas shift (RWGS) at 548–673 K and atmospheric pressure, using CO(2):H(2) = 1:1 and CO(2):H(2) = 1:3 mol/mol reactant mixtures. The support used determined the crystalline Mo(x)C phases obtained and the behavior of the supported nanostructured Mo(x)C catalysts in the RWGS. All catalysts were active in the RWGS reaction under the experimental conditions used; CO productivity per mol of Mo was always higher than that of unsupported Mo(2)C prepared using a similar method in the absence of support. The CO selectivity at 673 K was above 94% for all the supported catalysts, and near 99% for the SiO(2)-supported. The Mo(x)C/SiO(2) catalyst, which contains a mixture of hexagonal Mo(2)C and cubic MoC phases, exhibited the best performance for CO production.