Enhanced reductive transformation of p-chloronitrobenzene in a novel bioelectrode–UASB coupled system

Autor: Liang Zhu, Xiangyang Xu, Jie Jin, Jiaoqin Qi, Kaituo Gao
Rok vydání: 2014
Předmět:
Zdroj: Bioresource Technology. 167:303-309
ISSN: 0960-8524
Popis: 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 kgCOD m −3 d −1 and 60 g m −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 H 2 . Compared with the traditional UASB reactor (R1), the production of H 2 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.
Databáze: OpenAIRE