Overview on Photocatalytic and Electrocatalytic Pretreatment of Industrial Non-Biodegradable Pollutants and Pesticides

Abstract

Electrochemical and photochemical catalytic pretreatments were studied on diverse non-biodegradable industrial or toxic pollutants using different catalysts. This approach turned out also to be useful to degrade recalcitrant industrial waste waters markedly enhancing the biodegradability and biocompatibility of the treated effluents. In the case of p-toluenesulfonate, a completely non-biodegradable material from the dye industry, the TiO₂ photocatalytic material applied for two hours affected total dearomatization allowing efficient subsequent biological degradation. A photochemical-biological flow reactor has been built to attain full mineralization of large volumes of diluted solutions of this xenobiotics as found in polluted water reservoirs. Fenton and photo-Fenton systems have been extensively studied in the abatement of the highly soluble Orange azo-dyes. They induce rapid destructive and low cost degradation of these textile dyes comparable to flocculation/coagulation techniques.