Transition Metal B-Site Substitutions in LaAlO3 Perovskites Reorient Bio-Ethanol Conversion Reactions

LaAlO3 perovskites, as such and with 25% molar Al substitution by Cu, Co, or Ga, have been prepared sol-gel methods tested heterogeneous catalysts in the gas-phase conversion of ethanol. presented a significant acidic character, high formation ethylene ethanol dehydration. B-site substitutions increased basicity catalysts, favoring dehydrogenation to acetaldehyde. The most reducible Cu- Co-substituted materials, characterized easier surface oxygen vacancies, promoted self-condensation acetaldehyde Tishchenko mechanism, acetone odd-carbon number products. Aldol coupling acetaldehyde, favored on pure Ga-substituted LaAlO3, led butadiene hexadiene. role Ga insertion, both dehydration higher alcohols, corresponds an amphoteric character. olefins diolefins all suggests that LaAl-based materials present character among La-perovskites.