The effect of Pd content in LaMnO3 for methanol partial oxidation

Different loadings of Pd ions in the B-site position of LaMnO(3) perovskites were investigated under methanol partial oxidation (MPO). Compared to pure LaMnO(3), Pd-doped perovskites possessed greater reactivity. However, the correlation between Pd loadings with the catalytic activity of MPO was weak. The two Pd species, surface PdO and intracrystalline Pd ions, were identified. Surface PdO was proposed as being responsible for HCOH formation, CO conversion, and methanol combustion; nevertheless, the role of intracrystalline Pd ions in MPO chemistry was uncertain. Results show that incorporated Pd ions can vary the physicochemical properties of LaMnO(3) greatly, indicating their potential in MPO catalyst design. (C) 2011 Elsevier B.V. All rights reserved.