Applied Chemistry Department, Islamic Azad University, Karaj Branch, P.O. Box: 31485-313, Iran.
J Hazard Mater. 2011 Jun 15;190(1-3):119-24. doi: 10.1016/j.jhazmat.2011.03.010. Epub 2011 Mar 10.
The performance of an electrocoagulation (EC) process with aluminum/iron electrodes for removal of chromium on laboratory scale was studied. The effect of operational parameters such as initial pH, current density (CD), reaction time, initial concentrations (50, 100, 500, 1000 mg/L), solution conductivity, electrical energy consumption (EEC) and type of circuit were studied in an attempt to reach higher Cr(VI) removal efficiency. Alternating pulse current (APC) was used to prevent the passivity or polarization of electrodes. Important operating parameters were optimized to access higher (99%) Cr(VI) removal efficiency as follows: EEC range: 4-58 kW h/m(3) wastewater, CD: 56-222 A/m(2), operating time: 20-110 min, pH 3-9 (pH(optimum) 5), voltage: 15-25 V. NaCl, KCl, PAC (poly aluminum chloride), NaNO(3) were used as supporting electrolytes. NaCl as well as KCl handled the EC with the best performance in every aspect; however, PAC and NaNO(3) did not have the same results (Applied conductivity is better than literature). The results of this work are comparable with those of recent studies. Equal removal efficiency was obtained in "direct current" (DC) and (APC); however, when "APC" was used, water recovery (0.92 m(3)/m(3) wastewater) was significant and the turbidity was 1 NTU. "APC" amazed our experimental team.
研究了在实验室规模下使用铝/铁电极进行电凝聚（EC）过程去除铬的性能。研究了操作参数的影响，如初始 pH 值、电流密度（CD）、反应时间、初始浓度（50、100、500、1000mg/L）、溶液电导率、电能消耗（EEC）和电路类型，以试图达到更高的 Cr(VI)去除效率。采用交替脉冲电流（APC）来防止电极的钝化或极化。优化了重要的操作参数，以获得更高的（99%）Cr(VI)去除效率，如下所示：EEC 范围：4-58kW h/m(3)废水，CD：56-222A/m(2)，运行时间：20-110min，pH 3-9（最佳 pH 值为 5），电压：15-25V。NaCl、KCl、PAC（聚合氯化铝）、NaNO(3)被用作支持电解质。NaCl 和 KCl 在各个方面都表现出最佳的 EC 性能；然而，PAC 和 NaNO(3)则没有相同的结果（应用电导率优于文献）。这项工作的结果与最近的研究结果相当。在“直流”（DC）和（APC）中获得了相同的去除效率；然而，当使用“APC”时，水回收率（0.92m(3)/m(3)废水）显著，浊度为 1NTU。“APC”令我们的实验团队感到惊讶。
