Photoactivation of the oxidation process of <Emphasis Type="Italic">para</Emphasis>-chlorophenol in aqueous solutions

Kinetics of the oxidative destruction of para-chlorophenol in a combined iron-persulfate system under the action of simulated sunlight was studied. It was shown that, under additional photoirradiation, a deep conversion of chlorophenol and main intermediate products of its destruction is provided, with iron compounds serving not only as catalysts, but also as photochemical oxidation sensitizers. The degree of mineralization of para-chlorophenol and products of its oxidation under a photoactivated treatment for two hours reached a value of 60%, whereas that in the “dark” reaction did not exceed 1%. In the combined oxidizing system S₂O ₈ ^2– /Fe²⁺/UV-Vis, a considerable synergic effect was observed due to the formation of reactive oxygen intermediate both via decomposition persulfate and through reduction of Fe³⁺ from inactive Fe³⁺ intermediates.