Iranian Journal of Chemical Engineering (IJChE)

Abstract The SrO-CaO-Al₂O₃ nanocatalysts were prepared and optimized using the co-precipitation method. In this work parameters affecting the catalytic performance for the production of biodiesel from sunflower oil have been investigated. Thev response surface methodology (RSM) has been used to assess the impact of operational conditions on the production of biodiesel, with the biodiesel yield as the response variable. The catalyst was found to be calcined at 600 °C, with a 5-hour calcination time, 75 minutes of the aging time, and a precipitation temperature of 50 °C as optimal conditions for the production of biodiesel. The results showed that the optimal reaction conditions were CH₃OH/oil=12/1 at 60 ˚C with the concentration of 6wt.%of the catalyst and reaction time of 3 h at stirring speed of 600 rpm. Furthermore, the biodiesel yield reached 99% under optimal operational conditions. The SrO-CaO-Al₂O₃ nanocatalysts were characterized by using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transforms-infrared spectroscopy (FT-IR), and N₂adsorption–desorption measurements methods. The kinetic study has been done and the first order kinetic model was found  in agreement with experimental results (R²= 0.998). From the kinetic studies, E_a=41.57 kJ.mol^–1 and A= 5.25×10⁵ L.mol^-1s^-1 were obtained.