Sulfur resistant WGS catalyst for hydrogen production based on CoMo supported by Nb modified MgAl mixed oxide

In this paper, CoMo supported on Nb modified MgAl mixed oxide by calcination of layered double hydroxides (LDHs) were prepared using wet impregnation method. The fresh calcined catalysts were further sulfided by H2S/H2 and tested for water-gas shift reaction (WGSR). The physicochemical properties of fresh calcined catalysts were characterized by various adsorption and bulk techniques like XRD, ICP, N2-physisorption, CO2-TPD, H2-TPR, H2S-TPS and HRTEM. It is found that the addition of Nb does not affect the formation of LDHs, but changes the reduction and sulfidation behavior of Mo species on oxidic catalyst as well as the dispersion of MoS2 phase on the sulfided catalyst. The CoMo/Nb(5%)MgAl catalyst shows the lowest apparent sulfidation activation energy, consumes the highest amount of H2S and thus has the highest catalytic activity in WGS reaction.