Preparation of mesoporous polyoxometalate–tantalum pentoxide composite catalyst for efficient esterification of fatty acid

Mesoporous polyoxometalate–tantalum pentoxide composite catalyst, H3PW12O40/Ta2O5, was prepared by a one-step sol–gel-hydrothermal method in the presence of triblock copolymer surfactant. Structure, morphology and surface textural property of the composite were characterized. As-prepared H3PW12O40/Ta2O5 was applied as a solid acid catalyst for esterification reaction of lauric acid with ethanol, an important pretreatment step in the production of biodiesel from renewable feedstocks. Superiority of the H3PW12O40/Ta2O5 is highly active and selective to the esterification reaction, in addition, it is environmentally friendly and catalytically stable with resistance to leaching of the Keggin unit into reaction media.