Photocatalytic Destruction of Non-Ionic Surfactant Triton X-100 with Hydrogen Peroxide in Water in the Reactors with Immobilized TiO2

The photocatalytic destruction of organic substances is an efficient method for the production of high-quality purified water for various applications. For photocatalytic purposes, titania is most widely studied due to its low cost, availability, untoxicity, and stable chemical structure. The combined application of a photocatalyst and hydrogen peroxide increases the degree of ecotoxicants destruction to CO2, H2O, and inorganic ions (mineralization) and shortens the reaction time to decrease the water treatment expenditures. Photocatalytic destruction kinetics was studied for a non-ionic surfactant, namely, octylphenol ethoxylate (Triton X-100) with hydrogen peroxide in an aqueous medium in reactors with immobilized TiO2. The conditions for achieving a high degree of mineralization of Triton X-100 (84-88% for 4-5 h at C-0 = 50 mg/dm(3)) were established in the H2O2/TiO2/UV (lambda = 254 nm) system in a reactor with TiO2 immobilized on a large-pore ceramic support alongside with its essential advantages as compared to the TiO2/UV system, where the maximum degree of mineralization of Triton X-100 was 2.5 times lower. The possibility of attaining a high degree of mineralization with hydrogen peroxide for Triton X-100 (up to 92% on TOC basis of 2 h) was demonstrated in a quartz reactor with a Degussa P-25 TiO2 film on its inner surface at the external irradiation mode (lambda = 254 nm) without additional TiO2 powder.