Indirect photolysis of fumonisin B1 in aqueous medium

Abstract

Photochemical methods can be used for removing toxic organic pollutants in aqueous medium. These processes also include photolysis, where oxidation occurs through the use of UV or solar radiation, and can be in combination with some of the compounds: hydrogen peroxide (H2O2), ammonium persulfate (NH4)2S2O8, and potassium bromate (KBrO3). These processes are reactions of indirect photolysis. Generally, the effectiveness of homogeneous light-driven oxidation processes is associated with very reactive species, such as hydroxyl radicals (•OH), which can lead to complete mineralization of pollutants. The UV/H2O2 process is able to oxidize a wide variety of organic pollutants in aqueous solutions [1], but also the processes of persufate oxidation are receiving increasing attention in the treatment of pollutants in water [2]. In this paper, we have investigated efficiency of indirect photolysis of fumonisin B1 (FB1) in ultrapure water using UV and simulated solar radiation in the presence of H2O2 as well as (NH4)2S2O8. The effect of pH on the degradation efficiency was also examined. Degradation kinetics was monitored by high performance liquid chromatography with fluorescence detector technique using o-phthaldialdehyde 2-mercaptoethanol for derivatization of FB1. It was found that efficiency of degradation was the highest using of UV radiation in the presence of 1.36 × 10 5 mol/dm3 (NH4)2S2O8 at pH ~ 4. Namely, after 60 min of irradiation, the degradation of the FB1 was complete.