Highly efficient chloramphenicol degradation by UV and UV/H 2 O 2 processes based on LED light source
| Autor: | Shun Mao, Yulin Tang, Naiyun Gao, Mu Wang, Mengyi Wu, Bin Xu, Qianhong Liu, Shengji Xia, Zhenjiao Tan |
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| Rok vydání: | 2020 |
| Předmět: |
Chemistry
Ecological Modeling Chloramphenicol Radical 02 engineering and technology 010501 environmental sciences Photochemistry 01 natural sciences Pollution Light intensity Light source 020401 chemical engineering Photocatalysis medicine Environmental Chemistry Degradation (geology) Irradiation 0204 chemical engineering Health risk Waste Management and Disposal 0105 earth and related environmental sciences Water Science and Technology medicine.drug |
| Zdroj: | Water Environment Research. 92:2049-2059 |
| ISSN: | 1554-7531 1061-4303 |
| Popis: | In this study, UV-LED was employed as a novel light source to investigate the degradation of a representative antibiotic compound, chloramphenicol (CAP), in the absence or presence of H2 O2 . The UV-LED irradiation showed a higher capability for degradation of CAP than conventional UV-Hg vapor lamps. Effects of the initial CAP concentration, UV wavelength, and light intensity on the degradation of CAP by UV-LED were evaluated. Introduction of H2 O2 evidently enhanced the degradation efficiency of CAP due to the production of reactive hydroxyl radicals. Results showed that the UV-LED/H2 O2 removed CAP by up to 95% within 60 min at pH 5.0, which was twice as that achieved by the UV-LED alone. The degradation products were identified to propose plausible degradation pathways. Moreover, the formation potentials of typical carbonaceous disinfection by-products (C-DBPs) and nitrogenous disinfection by-products (N-DBPs) were assessed for the CAP polluted water treated by the UV-LED alone and UV-LED/H2 O2 processes. Results indicate unintended formation of certain DBPs, thereby highlighting the importance of health risk assessments before practical application. This study opens a new avenue for developing environment-friendly and high-performance UV-LED photocatalytic reactors for abatement of CAP pollution in water. PRACTITIONER POINTS: UV-LED bore higher capability to degrade CAP than low-pressure Hg lamp. The optimal performance to degrade CAP can be achieved at the UV wavelength of 280 nm. The degradation efficiency under UV-LED/H2 O2 process was double of that under UV-LED process. TCM, DCAN, and TCNM formation were higher under the existence of UV-LED radiation. The addition of H2 O2 had greater influence on the formation of DCAcAm than the introduction of UV-LED. |
| Databáze: | OpenAIRE |
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