Institute of Resource and Environment, Beijing Academy of Science and Technology, No. 1 Gao Li Zhang Road, Beijing, 100095, China.
Institute of Resource and Environment, Beijing Academy of Science and Technology, No. 1 Gao Li Zhang Road, Beijing, 100095, China.
Chemosphere. 2022 Sep;303(Pt 3):135249. doi: 10.1016/j.chemosphere.2022.135249. Epub 2022 Jun 9.
Electrocoagulation (EC) using iron (Fe), zinc (Zn) and aluminum (Al) electrodes was comparatively applied in the treatment of selenium (Se) in flour production (FP) wastewater. It was indicated that EC treatment with Fe anode obtained highest removal efficiency (79.1%) for Se in the 90 min treatment in the comparative study, which could be attributed to the superior adsorption capacity of in-situ generated iron flocs. Removal of Se resulted from electrodeposition and adsorption to in-situ generated flocs in EC treatment, and the operational conditions significantly influenced the Se removal performance in this work. The results showed the acidic condition and higher current density favored EC treatment on Se removal, EC removed up to 97.8% of Se at pH 4 under 15 mA cm, whereas it obtained 83.5% and 50.4% of removal efficiency at pH 7 and 10, respectively. There was competitive adsorption in the process of selenium removal, as the in-situ generated flocs effectively removed 35.6% of humic acid-like (HA-like) substance in FP wastewater after 90 min treatment. The FTIR results showed that HA-like substance mainly contained the protein water hydrogen bond, carboxylate COO antisymmetric stretching and other functional groups. Through the analysis of existence of Se in flocs and wastewater, it can be found that approximately 2.8%-3.92% of Se was removed by electrodeposition process. This study illustrated the Se removal mechanism and provided constructive suggestion for food manufacturing to the metal removal and utilization of advanced treatment.
电化学凝聚（EC）使用铁（Fe）、锌（Zn）和铝（Al）电极，被应用于面粉生产（FP）废水中硒（Se）的处理。研究表明，在 90 分钟的处理时间内，使用 Fe 阳极的 EC 处理对 Se 的去除效率最高（79.1%），这归因于原位生成的铁絮的优越吸附能力。EC 处理中 Se 的去除是通过电沉积和对原位生成絮体的吸附作用实现的，操作条件在这项工作中显著影响 Se 的去除性能。结果表明，酸性条件和更高的电流密度有利于 EC 对 Se 的去除，在 pH 值为 4 下，电流密度为 15 mA/cm²时，EC 去除了高达 97.8%的 Se，而在 pH 值为 7 和 10 时，去除效率分别为 83.5%和 50.4%。在 Se 去除过程中存在竞争吸附，因为原位生成的絮体在 90 分钟的处理后有效地去除了 FP 废水中 35.6%的类腐殖酸（HA-like）物质。FTIR 结果表明，HA-like 物质主要含有蛋白质水氢键、羧酸盐 COO 反对称伸缩等官能团。通过对絮体和废水中 Se 的存在进行分析，可以发现约有 2.8%-3.92%的 Se 是通过电沉积过程去除的。这项研究说明了 Se 的去除机制，并为食品制造业的金属去除和高级处理的利用提供了建设性的建议。
