Cu(OH)2纳米线/Cu网电极的制备及其还原水中硝酸盐性能研究

Preparation of Cu(OH)2 nanowire/ Copper mesh electrode and the performance of reducing nitrate in groundwater

中文关键词: 阳极氧化  Cu(OH)2纳米线  铜网阴极  硝酸盐还原  总氮去除

英文关键词: anodic oxidation  Cu(OH)2 nanowire  copper mesh cathode  nitrate reduction  total nitrogen removal

中文摘要:

      地下水中硝酸盐污染问题日益严重，电化学还原技术中铜作为阴极材料去除NO3--N存在活性位点少和吸附能力差的问题。本研究介绍了一种具有高长径比(120)的Cu(OH)2纳米线/Cu网电极材料应用于NO3--N的电催化还原。通过调控阳极氧化条件制备了铜基纳米材料，并通过对铜基纳米材料进行表征分析和去除NO3--N性能评估，确定25 ℃、1.0 mol/L NaOH和2.0 mA/cm2条件下阳极氧化的铜基纳米线材料电催化还原NO3--N效果最佳。在双池隔膜反应器中，以该电极为阴极，RuO2-IrO2-TiO2/Ti 为阳极，对NO3--N（50 mg/L）去除率达到98%，单位面积的NO3--N还原速率达到0.0111 min-1cm-2，是相同实验条件下未处理铜电极还原速率的6.5倍。为了实现总氮（TN）去除，采用单池反应器向体系中加1.0 g/L 的氯离子将阴极产生的氨氮进一步转化为氮气，TN去除率达到91%。循环实验结果显示该电极具有良好的稳定性。

英文摘要:

      Nitrate pollution in groundwater is increasingly serious. In electrochemical reduction technology, copper as a cathode material for NO3--N removal has the problems of few active sites and poor adsorption capacity. This study introduces a Cu(OH)2 nanowire/Cu mesh electrode material with high length-to-diameter ratio (120) for the electrocatalytic reduction of NO3--N. Firstly, the copper-based nanomaterials are prepared by adjusting the anodic oxidation conditions. Then, through the characterization and analysis of copper-based nanomaterials and the evaluation of NO3--N removal performance, the optimal anodization conditions for copper-based nanowires are determined to be 25 ℃, 1.0 mol/L NaOH and 2.0 mA/cm2. With this electrode as the cathode and RuO2-IrO2-TiO2/Ti as the anode, the removal rate of NO3--N (50 mg/L) reaches 98% in the double-diaphragm reactor. The NO3--N reduction rate of the cathode material per unit area reaches 0.0111 min-1cm-2, which is 6.5 times that of the untreated copper electrode under the same conditions. Finally, in order to achieve total nitrogen (TN) removal, 1.0 g/L chloride ion is used to further convert the ammonia nitrogen produced by the cathode into nitrogen in a single cell reactor, and the TN removal rate reaches 91%. The results of cycling experiments show that the electrode has good stability.