Applicability of the Photo-Fenton method for treating water containing pesticides

The Photo-Fenton process, i.e., the system Fe2+/H2O2/UV-Vis, was successful ly applied to a mixture of ten commercially available pesticides that serve d as a model for a proposed recycling plant for pesticide bottles. Experime nts with single pesticides revealed that although all of them were degradab le, there were remarkable differences concerning the reaction rate. Sunligh t driven pilot scale experiments with the complete mixture were conducted. For the pesticide mixture the initial pollutant concentration and the amoun t of iron was varied. The addition of oxalate and different modes of oxidan t addition were tested in order to improve the process. Thereby the reactio n rate was increased, while the final degree of TOC reduction was affected only slightly. All the experiments carried out were considerably faster tha n the previously published results of degradation tests that applied solar driven TiO2/UV and TiO2/Na2S2O8/UV photocatalysis. (C) 1999 Elsevier Scienc e B.V. All rights reserved.