Optimization of photocatalytic degradation of biodiesel using TiO₂/H₂O₂ by experimental design

This study reports on the investigation of the photodegradation of biodiesel (B100) in contact with water using TiO₂/H₂O₂. The TiO₂ was characterized by X-ray diffraction analysis (XRD), pH point of zero charge (pH_pzc) and textural analysis. The results of the experiments were fitted to a quadratic polynomial model developed using response surface methodology (RSM) to optimize the parameters. Using the three factors, three levels, and the Box-Behnken design of experiment technique, 15 sets of experiments were designed considering the effective ranges of the influential parameters. The responses of those parameters were optimized using computational techniques. After 24h of irradiation under an Hg vapor lamp, removal of 22.0% of the oils and greases (OG) and a 33.54% reduction in the total of fatty acid methyl ester (FAME) concentration was observed in the aqueous phase, as determined using gas chromatography coupled with flame ionization detection (GC/FID). The estimate of FAMEs undergo base-catalyzed hydrolysis is at least 3years (1095days) and after photocatalytic treatment using TiO₂/H₂O₂, it was reduced to 33.54% of FAMEs in only 1day.