A new insight into the degradation of CuEDTA with UV/H 2 O 2 was performed. It was found that the degradation was an UV-enhanced self-catalytic process with two main stages. The first was the induction stage in which cupric ions were produced in CuEDTA degradation with UV photolysis or/and H 2 O 2 oxidation . The second was the photo-catalytic degradation stage in which CuEDTA was oxidized by UV-enhanced cupric ion-based Fenton process. The degradation efficiency reached as high as 82.2% during 18 min, being 37.4 times higher than the efficiency sum of single H 2 O 2 oxidation and single UV photolysis. The enhancement effect can be contributed to the synergetic interaction between H 2 O 2 , cupric ion and UV, specially, to the excellent photo-activity of copper-peroxide intermediates. One of them was identified to be CuO 2 by analysis of its CE-C 4 D electropherograms, UV–vis adsorption spectra, FT-IR spectra, Raman spectra, especially XPS spectra. The enhancement mechanism was experimentally confirmed to be due to the acceleration of Cu(II)-to-Cu(I) transform by the photolysis of copper-peroxide intermediates, leading to the increasing CuEDTA degradation.
The Fe 0 /H 2 O 2 system, which is capable of removing organic matter from wastewater, suffers from limited efficiency because of slow Fe 2+ release and restricted Fe 2+ /Fe 3+ cycling. This study investigated the performance and mechanism of a UV-enhanced Fe 0 /H 2 O 2 system for the removal of organics in semiaerobic aged refuse biofilter (SAARB) effluent from landfill leachate, with HO • identified as the primary reactive oxygen species. UV not only initiates a homogeneous Fenton reaction through direct photolysis of H 2 O 2 and promotes Fe 2+ release from Fe 0 but also accelerates surface corrosion of Fe 0 to form more iron oxides, which react with H 2 O 2 in a heterogeneous Fenton reaction, thereby generating HO • at a faster rate. HO • preferentially reacts with organics containing chromophores or auxochromes, attacks humus with abundant conjugated structures, converts them into smaller organic molecules, and even achieves mineralization. Increasing the Fenton reagent ratio and dosage enhances the removal performance of the UV/Fe 0 /H 2 O 2 system, with optimal organic removal observed under acidic conditions. Ultimately, optimal conditions of the UV power (10 W), Fe 0 (2 mM) and H 2 O 2 (12 mM) dosages at pH 3.0 achieved 84.48% CN, 90.06% UV 254 , and 62.84% TOC removal. This study provides a feasible solution for achieving discharge standards for landfill leachate.
危险品化学品经营许可证（带存储）