International audienceThe aim of this study is the evaluation of niobium catalysts (niobic acid, niobium phosphate) in the esterification reactions of fatty acids (C12-C18) with alcohols (methanol, ethanol, butanol). The catalysts were characterized by different techniques (N2 adsorption/desorption, XRD, FTIR, FTIR of adsorbed pyridine). The niobium phosphate was the most active in esterification of lauric acid with butanol and can be reutilized three times without loss of activity