title: Efficient transformation of DDTs with Persulfate Activation by Zero-valent Iron Nanoparticles: A Mechanistic Study.
abstract: In this study, persulfate (PS) activation by nano-Fe(0) was used to degrade dichlorodiphenyltrichloroethane (DDT), and the mechanism of this process was elucidated with EPR, GC-MS and free-radical quenching studies. It was found that DDT was degraded efficiently in PS/nano-Fe(0), and GC-MS analysis showed that benzoic acid, benzyl alcohol, dichlorobenzophenone and 2,2-bis(p-chlorophenyl)-ethane were the dominant products of DDT degradation, while only dechlorination products (DDD and DDE) were observed in nano-Fe(0) without persulfate. EPR results showed that persulfate activation by nano-Fe(0) led to the production of more sulfate radicals and hydroxyl radicals, which accounted for DDT degradation. But the free radical quenching studies suggested that the addition of ethanol to PS/nano-Fe(0) favored the reductive dechlorination of DDT, which was ascribed that the formed ethanol radical (CH(CH3)OH) enhanced the reductive dechlorination of DDT. Furthermore, the nano-Fe(0) loading not only affected the degradation efficiency of DDT, but also influenced the intermediate product distribution of DDT degradation in the PS/nano-Fe(0) process.
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Changyin
authors.initials: C
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China. Electronic address: gdfang@issas.ac.cn.
authors.forename: Guodong
authors.initials: G
authors.lastname: Fang
authors.affiliation: Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0071, USA.
authors.forename: Dionysios D
authors.initials: DD
authors.lastname: Dionysiou
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China.
authors.forename: Cun
authors.initials: C
authors.lastname: Liu
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China.
authors.forename: Juan
authors.initials: J
authors.lastname: Gao
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Wenxiu
authors.initials: W
authors.lastname: Qin
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, PR China. Electronic address: dmzhou@issas.ac.cn.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Zhou
keywords: Activation; DDT degradation; Free radicals; Nano-Fe(0); Persulfate