Abstract The mechanism of the catalytic reduction of palmitic acid to n-pentadecane at 260 C in the presence of hydrogen over catalysts combining multiple functions has been explored. The reaction involves rate-determining reduction of the carboxylic group of palmitic acid to give hexadecanal, which is catalyzed either solely by Ni or synergistically by Ni and the ZrO 2 support. The latter route involves adsorption of the carboxylic acid group at an oxygen ...