Advanced Water Management Centre, The University of Queensland, St. Lucia, QLD 4072, Australia.
Environ Sci Technol. 2009 Nov 15;43(22):8690-5. doi: 10.1021/es9020266.
Nitrobenzene occurs as a pollutant in wastewaters originating from numerous industrial and agricultural activities. It needs to be removed prior to discharge to sewage treatment works because of its high toxicity and persistence. In this study, we investigated the use of a bioelectrochemical system (BES) to remove nitrobenzene at a cathode coupled to microbial oxidation of acetate at an anode. Effective removal of nitrobenzene at rates up to 1.29 +/- 0.04 mol m(-3) TCC d(-1) (total cathodic compartment, TCC) was achieved with concomitant energy recovery. Correspondingly, the formation rate for the reduction product aniline was 1.14 +/- 0.03 mol m(-3) TCC d(-1). Nitrobenzene removal and aniline formation rates were significantly enhanced when the BES was supplied with power, reaching 8.57 +/- 0.03 and 6.68 +/- 0.03 mol m(-3) TCC d(-1), respectively, at an energy consumption of 17.06 +/- 0.16 W m(-3) TCC (current density at 59.5 A m(-3) TCC). Compared to those of conventional anaerobic biological methods for nitrobenzene removal, the required dosage of organic cosubstrate was significantly reduced in this system. Although aniline was always identified as the major product of nitrobenzene reduction at the cathode of BES in this study, the Coulombic efficiencies of nitrobenzene removal and aniline formation were dependent on the current density of the BES.
硝基苯作为一种污染物存在于许多工业和农业活动产生的废水中。由于其高毒性和持久性，在排放到污水处理厂之前需要将其去除。在这项研究中，我们研究了使用生物电化学系统（BES）在阴极去除硝基苯，同时在阳极进行乙酸的微生物氧化。通过阴极耦合微生物氧化乙酸，有效去除了高达 1.29 +/- 0.04 mol m(-3) TCC d(-1)（总阴极室，TCC）的硝基苯，同时实现了能量回收。相应地，还原产物苯胺的生成速率为 1.14 +/- 0.03 mol m(-3) TCC d(-1)。当 BES 供电时，硝基苯去除率和苯胺生成速率显著提高，分别达到 8.57 +/- 0.03 和 6.68 +/- 0.03 mol m(-3) TCC d(-1)，能量消耗为 17.06 +/- 0.16 W m(-3) TCC（电流密度为 59.5 A m(-3) TCC）。与传统的用于去除硝基苯的厌氧生物方法相比，该系统所需的有机共底物剂量显著减少。尽管在这项研究中，BES 阴极总是将苯胺鉴定为硝基苯还原的主要产物，但硝基苯去除和苯胺形成的库仑效率取决于 BES 的电流密度。
