TY - JOUR
T1 - Removal and transformation of polycyclic aromatic hydrocarbons during electrocoagulation treatment of an industrial wastewater
AU - Gong, Chenhao
AU - Shen, Gang
AU - Huang, Haiou
AU - He, Peiran
AU - Zhang, Zhongguo
AU - Ma, Baoqing
N1 - Funding Information:
The authors greatly appreciate the financial support of the Special Funds for Technological Development of Research Institutes from the Ministry of Science and Technology of China ( 2013EG111129 ), the Program for Youth Scientists of the Beijing Academy of Science and Technology ( 201505 ), the 2016 BJAST Reform and Development Program and the Special Fund of the State Joint Key Laboratory for Environmental Simulation and Pollution Control ( 270403GK ).
Publisher Copyright:
© 2016 Elsevier Ltd
PY - 2017/2/1
Y1 - 2017/2/1
N2 - Polycyclic aromatic hydrocarbons (PAHs) are an important class of water pollutants because of their known ecological and human toxicity. Electrocoagulation (EC) is a promising technology for mitigating industrial wastewater pollution, but the removal and transformation of PAHs during EC treatment has not yet been understood. Therefore, a paper-making wastewater effluent (PMWW) was employed in this study to investigate the relationship between PAHs’ removal and transformation during EC treatment. The results show that 86% of PAHs were effectively removed not only by the electro-oxidation reactions, but also by adsorption onto Fe hydroxide flocs. The removal and transformation of PAHs were related to the number of rings in their structures. Some PAHs composed of two aromatic rings (e.g., naphthaline and dimethylnaphthalene) were produced from humic acid-like and fulvic acid-like organics in PMWW, while PAHs with three to four rings were degraded, thus being removed efficiently. Therefore, PAH transformation during EC treatment exerted double-sided effects on the removal of PAHs; the net effect appeared to be positive. Overall, this study revealed the existence and importance of PAH transformation during EC treatment and provided useful guidance for pulp and paper mills to improve the design and operation of wastewater treatment facilities.
AB - Polycyclic aromatic hydrocarbons (PAHs) are an important class of water pollutants because of their known ecological and human toxicity. Electrocoagulation (EC) is a promising technology for mitigating industrial wastewater pollution, but the removal and transformation of PAHs during EC treatment has not yet been understood. Therefore, a paper-making wastewater effluent (PMWW) was employed in this study to investigate the relationship between PAHs’ removal and transformation during EC treatment. The results show that 86% of PAHs were effectively removed not only by the electro-oxidation reactions, but also by adsorption onto Fe hydroxide flocs. The removal and transformation of PAHs were related to the number of rings in their structures. Some PAHs composed of two aromatic rings (e.g., naphthaline and dimethylnaphthalene) were produced from humic acid-like and fulvic acid-like organics in PMWW, while PAHs with three to four rings were degraded, thus being removed efficiently. Therefore, PAH transformation during EC treatment exerted double-sided effects on the removal of PAHs; the net effect appeared to be positive. Overall, this study revealed the existence and importance of PAH transformation during EC treatment and provided useful guidance for pulp and paper mills to improve the design and operation of wastewater treatment facilities.
KW - Electrochemical degradation
KW - Electrocoagulation
KW - Excitation-emission matrix
KW - Polycyclic aromatic hydrocarbons
KW - Transformation
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U2 - 10.1016/j.chemosphere.2016.10.044
DO - 10.1016/j.chemosphere.2016.10.044
M3 - Article
C2 - 27776239
AN - SCOPUS:84994030746
SN - 0045-6535
VL - 168
SP - 58
EP - 64
JO - Chemosphere
JF - Chemosphere
ER -