title: Reductive transformation and detoxification mechanism of 2,4-dinitrochlorobenzene in combined zero valent iron and anaerobic-aerobic process.
abstract: A combined zero valent iron (ZVI) and anaerobic-aerobic process was adopted for the treatment of 2,4-dinitrochlorobenzene (DNCB)-containing wastewater. The transformation pathway, reduction of acute toxicity and enhancement of biodegradability were investigated. After pretreatment by ZVI, DNCB in wastewater could be completely converted into 2,4-diaminochlorobenzene (DACB). The ratio of BOD5/COD increased from 0.005 +/- 0.001 to 0.168 +/- 0.007, while EC(50, 48 hr) (V/V) increased from 0.65% to 5.20%, indicating the enhancement of biodegradability and reduction of acute toxicity with the pretreatment by ZVI. DACB was further dechlorinated to m-phenylenediamine during the anaerobic process using methanol as electron donor, with EC(50, 48 hr) increasing from 5.20% to 48.2%. After the subsequent anaerobic-aerobic process, m-phenylenediamine was degraded completely, with effluent COD of 67.5 +/- 10.8 mg/L. This effluent of the subsequent anaerobic-aerobic process was not toxic to zebrafish. The combined ZVI and anaerobic-aerobic process offers bright prospects for the treatment of chlorinated nitroaromatic compound-containing wastewater.
authors.affiliation: Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China. shenjinyou@mail.njust.edu.cn
authors.forename: Jinyou
authors.initials: J
authors.lastname: Shen
authors.forename: Zongyuan
authors.initials: Z
authors.lastname: Zhou
authors.forename: Changjin
authors.initials: C
authors.lastname: Ou
authors.forename: Xiuyun
authors.initials: X
authors.lastname: Sun
authors.forename: Jiansheng
authors.initials: J
authors.lastname: Li
authors.forename: Weiqing
authors.initials: W
authors.lastname: Han
authors.forename: Lin
authors.initials: L
authors.lastname: Zhou
authors.forename: Lianjun
authors.initials: L
authors.lastname: Wang
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D019149:Bioreactors; D004137:Dinitrochlorobenzene / Q000737:chemistry* / Q000378:metabolism*; D007501:Iron / Q000737:chemistry*; D015394:Molecular Structure; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D004137:Dinitrochlorobenzene; D014874:Water Pollutants, Chemical; D007501:Iron