Photochemical oxidation of priority ecotoxicants of gold mill wastewater

[摘要] The kinetic regularities of the photodestruction process of hexacyanoferrates using sources of mono- and polychromatic UV radiation with different spectral ranges are studied. The comparative experiments on the degradation of hexacyanoferrates in direct photolysis showed that the efficiency of the degradation process changed in the order UV-Vis > UV-222 > UV- Xe > UV-254. It was found that with the UV treatment of hexacyanoferrate-containing solutions in combination with persulfate (oxidation system {UV/S2O8 2- }), the specific conversion of the substance changed in the order UV-222/S2O8 2- > UV-Xe/S2O8 2- > UV- 254/S2O8 2- > UV-Vis/S2O8 2- . The high destruction efficiency of hexacyanoferrates with the use of the oxidizing system {UV/S2O8 2- } is due to both generating in situ active oxygen species - hydroxyl and sulfate anion radicals, and the disproportionation of persulfate by Fe2+ / Fe3+ ions, released during the destruction of the hexacyanoferrate complex.

[发布机构] Baikal Institute of Nature Management, Siberian Branch, Russian Academy of Sciences, Sakhyanovoy St. 6, Ulan-Ude, Russia^1

[学科分类] 土木及结构工程学

[关键词] Active oxygen species;Comparative experiments;Degradation process;Destruction efficiency;Disproportionations;Kinetic regularities;Photochemical oxidation;Polychromatic UV radiation