Catalytic activity of mesoporous V/SBA-15 in the transesterification and esterification of fatty acids

Mesoporous V/SBA-15 with different weight percentages (1, 2.5 and 5 wt%) of vanadia was prepared via the wet impregnation method. The mesoporous nature of the catalysts were investigated, using the X-ray diffraction analysis, N-2 adsorption-desorption isotherm and scanning electron microscope. All the catalysts showed the highly dispersed vanadia was confirmed by the result of the diffuse reflectance UV vis technique. From the NH3-temperature programmed desorption, it is observed that, the acidity values of the prepared catalysts are in the range 72-102 A mu mol/g. 5 % V/SBA-15, possesses Bronsted and Lewis acid sites ensured by pyridine-adsorbed Fourier-transform infrared method. The acidity of the catalyst was experimented in the transesterification of sunflower oil. The reaction conditions were optimized with maximum conversion (100 %) of sunflower oil into biodiesel and the activity of the catalyst was found to be more in 5 wt% V/SBA-15 at 140 A degrees C. Different fatty acids like butyric, valeric, caprylic and oleic acid were also studied under optimized conditions, and the isolated product was confirmed from the H-1 NMR spectroscopy.