The critical role of the operating conditions on the Fenton oxidation of 2-chlorophenol: Assessment of PCDD/Fs formation

JOURNAL OF HAZARDOUS MATERIALS

卷:279

Article

Vallejo, Marta¹  San Roman, M. Fresnedo¹  Ortiz, Inmaculada¹  Irabien, Angel¹ 

[1] Univ Cantabria, ETSIIyT, Dept Ingenierias Quim & Biomol, E-39005 Santander, Spain

关键词: 2-Chlorophenol;    Fenton oxidation;    Hydrogen peroxide dose;    Temperature effect;    Chloride influence;    PCDD/Fs formation;   

DOI  :  10.1016/j.jhazmat.2014.07.020

来源: Elsevier

【 摘 要 】

This work assesses the influence of the operating conditions H2O2 dose (20 or 100% of the stoichiometric amount), temperature (20 or 70 degrees C), and the presence of chloride in the oxidation medium in the formation of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during Fenton treatment of aqueous samples of 2-chlorophenol, 2-CP, one of the strongest precursor of PCDD/Fs. After 4h of oxidation in the experiments carried out with 20% H2O2 chlorinated phenoxyphenols and biphenyls, which are intermediates in PCDD/Fs formation, as well as PCDD/Fs were observed, resulting in concentrations 11 times higher than in the untreated sample. Additionally, when NaCl was also present in the reaction medium, PCDD/Fs were formed at higher extent, with a total concentration 74.4 times higher than in the untreated 2-CP solution. Results depicted a preferential formation of PCDFs over PCDDs, with dominance of lower chlorinated PCDD/Fs (tetra and penta-PCDD/Fs). Besides, the formation of the most toxic PCDD/Fs congeners (2,3,7,8-PCDD/Fs) was not favored under the operating conditions used in this work. (C) 2014 Elsevier B.V. All rights reserved.

【 授权许可】

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