Catalytic combustion of methanol over La, Mn-hexaaluminate catalysts

• La,Mn-hexaaluminate catalysts prepared by two simple methods and treated at 1300 °C
• Higher thermal stability for catalysts made by coprecipitation vs. solution combustion
• Hexaaluminates without noble metals display good activity for methanol combustion.
• Partial substitution of Sr for La improves methanol deep oxidation activity.
• A strong correlation exists between lattice oxygen mobility and catalytic performance.

The work investigated the development of thermally stable and cheap catalysts without noble metals for the high temperature combustion of methanol in low emission burners for heat and power generation units. LaMnAl11O19, La0.8Sr0.2MnAl11O19, and LaMn0.5Mg0.5Al11O19 hexaaluminates were prepared by two alternative, relatively cheap methods, namely the Solution Combustion synthesis with Urea, and the Carbonates Coprecipitation route. Calcination temperature as high as 1300 °C was selected in order to assess the stability of the catalytic deep oxidation activity which is required to keep the combustion reaction self-sustained. All of the catalysts were characterized by XRD, BET, and H2-TPR, and the intrinsic catalytic activity and selectivity for the deep oxidation of methanol were investigated in light of their structural and redox properties.