CSIR- National Environmental Engineering Research Institute, Nagpur, Maharashtra, India.
CSIR- National Environmental Engineering Research Institute, Nagpur, Maharashtra, India; Central University of Jharkhand, Ranchi, Jharkhand, India.
Chemosphere. 2020 Jul;251:126437. doi: 10.1016/j.chemosphere.2020.126437. Epub 2020 Mar 7.
Treatment of mixed industrial wastewater is a challenging task due to its high complexity. This work scrutinizes the electrochemical treatment of mixed industrial wastewater, specifically electrocoagulation and indirect electrochemical oxidation processes through COD and color removal studies. Both processes are found to be more efficient at the wastewater pH. Monopolar connection was found more effective than bipolar connection for the removal of COD and color from wastewater. The monopolar connection removed COD up to 55% and color 56% whereas bipolar connection leads to the removal of 43% and 48% respectively at wastewater pH with an applied voltage 1.5 V in the course of 1 h of electrolysis. In the case of indirect electrochemical oxidation process using graphite electrodes, the COD and color abatement efficiencies of the indirect electrochemical oxidation process were found as 55% and 99.8%, respectively within 1 h of electrolysis conducted at pH 7.7, applied voltage 4 V, and NaCl concentration 1 g L. This work also highlights the importance of the presence of electrolytes in the indirect electrochemical oxidation process as the external addition of sodium chloride significantly enhanced both COD and color elimination efficiency.
处理混合工业废水是一项具有挑战性的任务，因为其复杂性很高。本工作研究了混合工业废水的电化学处理，特别是通过 COD 和颜色去除研究的电絮凝和间接电化学氧化过程。这两种方法在废水 pH 值下都被发现更有效。与双极连接相比，单极连接在去除废水中的 COD 和颜色方面更有效。单极连接可去除高达 55%的 COD 和 56%的颜色，而双极连接在 1 小时电解过程中在废水 pH 值为 1.5 V 时分别导致 43%和 48%的去除。在使用石墨电极的间接电化学氧化过程中，在 pH 值为 7.7、施加电压为 4 V 和 NaCl 浓度为 1 g·L 的条件下进行 1 小时电解，间接电化学氧化过程的 COD 和颜色去除效率分别为 55%和 99.8%。本工作还强调了电解质在间接电化学氧化过程中的重要性，因为外部添加氯化钠显著提高了 COD 和颜色消除效率。
