Department of Civil and Environmental Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashihiroshima 739-8527, Japan.
Int J Environ Res Public Health. 2018 Jul 9;15(7):1443. doi: 10.3390/ijerph15071443.
Eliminating organic and inorganic pollutants from water is a worldwide concern. In this study, we applied electrochemical oxidation (EO) and adsorption techniques to eliminate ammonia, phenols, and Mo(VI) from aqueous solutions. We analyzed the first stage (EO) with response surface methodology, where the reaction time (1⁻3 h), initial contaminant concentration (10⁻50 mg/L), and pH (3⁻6) were the three independent factors. Sodium sulfate (as an electrolyte) and Ti/RuO₂⁻IrO₂ (as an electrode) were used in the EO system. Based on preliminary experiments, the current and voltage were set to 50 mA and 7 V, respectively. The optimum EO conditions included a reaction time, initial contaminant concentration, and pH of 2.4 h, 27.4 mg/L, and 4.9, respectively. The ammonia, phenols, and Mo elimination efficiencies were 79.4%, 48.0%, and 55.9%, respectively. After treating water under the optimum EO conditions, the solution was transferred to a granular composite adsorbent column containing bentonite, limestone, zeolite, cockleshell, activated carbon, and Portland cement (i.e., BAZLSC), which improved the elimination efficiencies of ammonia, phenols, and molybdenum(VI) to 99.9%. The energy consumption value (8.0 kWh kg N) was detected at the optimum operating conditions.
从水中去除有机和无机污染物是全世界共同关注的问题。本研究采用电化学氧化（EO）和吸附技术从水溶液中去除氨、酚和 Mo(VI)。我们采用响应面法对第一阶段（EO）进行了分析，其中反应时间（1⁻3 h）、初始污染物浓度（10⁻50 mg/L）和 pH（3⁻6）是三个独立因素。EO 系统中使用了硫酸钠（作为电解质）和 Ti/RuO₂⁻IrO₂（作为电极）。根据初步实验，电流和电压分别设定为 50 mA 和 7 V。EO 的最佳条件包括反应时间、初始污染物浓度和 pH 值分别为 2.4 h、27.4 mg/L 和 4.9。氨、酚和 Mo 的去除效率分别为 79.4%、48.0%和 55.9%。在最优 EO 条件下处理水后，将溶液转移到含有膨润土、石灰石、沸石、贝壳、活性炭和波特兰水泥的颗粒复合吸附柱（BAZLSC）中，将氨、酚和钼（VI）的去除效率提高到 99.9%。在最佳运行条件下，检测到的能耗值（8.0 kWh kg N）。
