Evaluation of chalcones in the biodiesel oxidative process

The main idea of this study is to evaluate different chalcones as antioxidant for sunflower biodiesel. Sunflower oil transesterification was carried out by ultrasound-assisted basic catalysis, 98.5 % conversion was obtained. Physicochemical parameters (viscosity, acid, iodine and saponification values) were evaluated to determine the biodiesel quality. The fatty acid profile was determined by gas chromatography with flame ionization detection (GC-FID). Eleven chalcones having different substituents were synthesized, characterized by Fourier transform infrared (FT-IR) and gas chromatography coupled to mass spectrometry (GC-MS), and their purities were determined by GC-MS and melting point. The evaluation of the antioxidant activity of these chalcones was performed using the methods of DPPH and chemiluminescence, the chalcones that showed the highest antioxidant activity in in vitro tests were added to biodiesel, wich had its oxidative stability measured in Rancimat