Activated Carbons for Hydrothermal Decarboxylation of Fatty Acids

We converted palmitic and oleic acids to fuel range hydrocarbons using two activated carbons in near- and supercritical water with no H2 added. The main products from palmitic acid were C8−C15 n-alkanes. The major products from oleic acid were C12−C17 n-alkanes and some C17 olefins. The pseudo-first-order rate constants displayed Arrhenius behavior. The apparent activation energy of 125 kJ/mol for palmitic acid decarboxylation is higher than that observed with a 5% Pt/C catalyst. Nevertheless, these results show that activated carbons possess catalytic activity for the hydrothermal decarboxylation of fatty acids.