CHEMICAL AND BIOCHEMICAL ENGINEERING QUARTERLY, cilt.33, ss.43-57, 2019 (SCI İndekslerine Giren Dergi)
Sonication-assisted photo-Fenton oxidation of an endocrine disrupting compound, bisphenol-A (BPA), was studied under visible-light irradiation in the presence of a LaFeO3 perovskite catalyst. The effects of the parameters: initial BPA concentration ([BPA](0)), H2O2 concentration ([H2O2](0)), catalyst loading, initial pH of the BPA solution, and reaction temperature were studied on the sonication-assisted photo-Fenton oxidation of an aqueous BPA solution. The optimum conditions for the oxidation were determined to be: [BPA](0) = 10 ppm, [H2O2](0) = 4.8 mM, catalyst loading = 0.75 g L-1, pH = 2.6, temperature = 313 K. During all runs, sonication power of 40 W, visible lights power of 150 W+150 W, BPA solution volume (0.5 L), and stirring speed of 500 rpm were kept constant. Under these conditions, degradation of 56.3 %, COD removal of 50.9 %, and TOC removal of 15.6 % were achieved after 6 h of reaction. The small amount of iron that leached into the solution indicated high stability of the catalyst. The sonication-assisted photo-Fenton oxidation of BPA was described by the second order kinetics with an activation energy of 15.34 kJ mol(-1). Toxicity tests were also performed and the results revealed that the intermediates formed in the sonication-assisted photo-Fenton oxidation of BPA were less toxic compared to the parent BPA molecule at a neutral pH value. However, the same interpretation was not valid at the acidic pH of 2.6.