This work investigated the synthesis, structural and spectroscopic characterization and analysis of the catalytic potential of SrTiO3 perovskite catalysts and Sr1-xKxTiCux/2O3 double perovskites, where x = 0.2, 0.3 and 0.5, in the preparation of biodiesel via the ethyl route. From the host structure of strontium titanate SrTiO3, solid solutions containing copper and potassium atoms with the following stoichiometries were investigated: Sr0.8K0.2TiCu0.1O3,...