Methanol partial oxidation over palladium-, platinum-, and rhodium-integrated LaMnO3 perovskites

This study investigates methanol partial oxidation over LaMnO3 and LaMn0.95B0.05O3 (B = Pd, Pt, and Rh) perovskites. Their surface and bulk properties were characterized by appropriate physicochemical techniques including BET surface area measurement, XRD, EDS, XPS, H2-TPR, TPO, O2-TPD, and CH3OH-TPD. Results show significant differences in reducibility and oxygen activity between promoted and untainted LaMnO3. Promoted perovskites showed higher reactivity than pure LaMnO3. Results suggest that a redox pathway enhances partial oxidation to formaldehyde while oxygen activity, particularly surface chemisorbed oxygen, plays a central role in combustion. This study also reveals a plausible reaction mechanism of methanol partial oxidation over LaMnO3-based perovskites.

Graphical abstract. By incorporating trace Pd, Pt, or Rh ions in the B-site position, catalytic performances of methanol partial oxidation over LaMnO3 based perovskites can be varied substantially.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► The B-site of LaMnO3 perovskites was substituted by trace of Pd, Pt, and Rh ions. ► Catalysts for partial oxidation of methanol. ► Reducibility and oxygen mobility can be improved by the B-site-ion replacement. ► Reaction pathways can be manipulated diversely by the integrated promoter.