title: Enhanced reductive transformation of p-chloronitrobenzene in a novel bioelectrode-UASB coupled system.
abstract: The laboratory-scale upflow anaerobic sludge blanket (UASB) reactor equipped with a pair of bioelectrodes was established for the enhancement of p-chloronitrobenzene (p-ClNB) reductive transformation via the electrolysis. Results showed that a stable COD removal efficiency over 99% and high p-ClNB transformation rate of 0.328 h(-1) were achieved in the bioelectrode-UASB coupled system with influent COD and p-ClNB loading rates of 2.1-4.2 kg COD m(-3)d(-1) and 60 gm(-3)d(-1), respectively. The bioelectrodes were supplied with a voltage of 2.5-5.0 V and the effective current was above 2 mA, which resulted in a continuous supply of H2. Compared with the traditional UASB reactor (R1), the production of H2 was promoted in the bioelectrode-UASB coupled system (R2), and was consumed as an internal electron donor for p-ClNB reductive transformation by anaerobic microbes simultaneously. Furthermore, the cyclic voltammetry curve (CV) analysis of biocathodes showed a positive shift in the reductive peak potential and a dramatic increase in the reductive peak current, which demonstrated the catalytic reduction of p-ClNB by biocathode in the combined system.
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China. Electronic address: felix79cn@hotmail.com.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Kaituo
authors.initials: K
authors.lastname: Gao
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Yixing Urban Supervision and Inspection Administration of Product Quality, National Supervision and Inspection Center of Environmental Protection Equipment Quality, Yixing 214205, China.
authors.forename: Jiaoqin
authors.initials: J
authors.lastname: Qi
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Jin
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety, Hangzhou 310058, China. Electronic address: xuxy@zju.edu.cn.
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Xu
mesh_terms: D000693:Anaerobiosis; D061249:Batch Cell Culture Techniques; D001673:Biodegradation, Environmental; D001674:Bioelectric Energy Sources; D019149:Bioreactors / Q000382:microbiology*; D055664:Electrochemical Techniques; D004566:Electrodes; D005740:Gases / Q000032:analysis; D006859:Hydrogen / Q000378:metabolism; D008697:Methane / Q000096:biosynthesis; D009578:Nitrobenzenes / Q000378:metabolism*; D010084:Oxidation-Reduction; D012722:Sewage / Q000382:microbiology*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification
chemical_list: D005740:Gases; D009578:Nitrobenzenes; D012722:Sewage; D014874:Water Pollutants, Chemical; D006859:Hydrogen; C010407:4-chloronitrobenzene; D008697:Methane
keywords: Anaerobic sludge; Bioelectrode; Enhancement; Reductive transformation; p-Chloronitrobenzene (p-ClNB)