Gavazza Sávia, Guzman Juan J L, Angenent Largus T
Department of Biological and Environmental Engineering, Cornell University, Riley Robb Hall, Ithaca, NY, 14853, USA,
Biodegradation. 2015 Apr;26(2):151-60. doi: 10.1007/s10532-015-9723-8. Epub 2015 Mar 8.
Azo dyes are the most widely used coloring agents in the textile industry, but are difficult to treat. When textile effluents are discharged into waterways, azo dyes and their degradation products are known to be environmentally toxic. An electrochemical system consisting of a graphite-plate anode and a stainless-steel mesh cathode was placed into a lab-scale anaerobic bioreactor to evaluate the removal of an azo dye (Direct Black 22) from synthetic textile wastewater. At applied potentials of 2.5 and 3.0 V when water electrolysis occurs, no improvement in azo dye removal efficiency was observed compared to the control reactor (an integrated system with electrodes but without an applied potential). However, applying such electric potentials produces oxygen via electrolysis and promoted the aerobic degradation of aromatic amines, which are toxic, intermediate products of anaerobic azo dye degradation. The removal of these amines indicates a decrease in overall toxicity of the effluent from a single-stage anaerobic bioreactor, which warrants further optimization in anaerobic digestion.
偶氮染料是纺织工业中使用最广泛的着色剂，但难以处理。当纺织废水排放到水道中时，已知偶氮染料及其降解产物具有环境毒性。将由石墨板阳极和不锈钢网阴极组成的电化学系统置于实验室规模的厌氧生物反应器中，以评估从合成纺织废水中去除偶氮染料（直接黑22）的效果。在发生水电解时施加2.5伏和3.0伏的电势时，与对照反应器（带有电极但未施加电势的集成系统）相比，未观察到偶氮染料去除效率的提高。然而，施加这种电势会通过电解产生氧气，并促进芳香胺的好氧降解，芳香胺是厌氧偶氮染料降解的有毒中间产物。这些胺的去除表明单级厌氧生物反应器流出物的总体毒性降低，这值得在厌氧消化中进一步优化。
