Lewis Acid Promoted Sustainable Transformation of Triglycerides to Fatty Acids Using a Water-Tolerant Nb2O5 Catalyst

Valorization of biomass-derived feedstock triglycerides (TGs) into the corresponding acids via hydrolysis is an attractive and robust research target. Herein we screened different heterogeneous and homogeneous catalysts for the hydrolysis of trilaurin in water; among the catalysts, the pseudohexagonal (TT) phase Nb2O5 catalyst was the most effective with the highest yield of lauric acid under mild reaction conditions. A series of Nb2O5 catalysts obtained by calcinating Nb2O5·nH2O at different temperatures were characterized and tested for this hydrolysis reaction to determine the structure–activity relationship. In situ IR studies suggested that the reaction progress and catalytic activity depend on activating the ester carbonyl bond by Lewis acid sites of the catalysts. A catalytic study showed that the present method possesses the advantages of easy operation and recyclability of the catalyst, no need for any additives, applicable to various triglycerides with high yield (up to 99%), and high turnover numbers (up to 3880).