苯酚在Ti/IrO_2-Ta_2O_5电极上的电化学反应

采用循环伏安法研究了苯酚在Ti/IrO_2-Ta_2O_5电极上的电化学反应行为,通过高效液相色谱(HPLC)、总有机碳(TOC)测定仪、化学需氧量(COD)消解装置研究了该电极降解苯酚的效能。结果表明:苯酚在Ti/Ir O2-Ta2O5电极上的电化学反应主要发生在析氧反应区,而较高浓度苯酚可发生少量的不可逆的直接电化学氧化反应。在支持电解质浓度为5 g·L~(-1)、苯酚初始浓度100 mg·L~(-1)时,可获得较大的氧化峰电流和较高的电荷利用率。在苯酚初始浓度100 mg·L~(-1),电解质浓度5 g·L~(-1),反应时间120min,电流40 m A的适宜操作条件下,苯酚、COD、TOC去除率和平均电流效率(ACE)可分别达82%、49%、39%和24.5%。

Electrochemical Reaction for Phenol on Ti/IrO2-Ta2O5 Electrode

The electrochemical reaction behaviors of phenol on Ti/IrO₂-Ta₂O₅ electrode were investigated by cyclic voltammetry. The efficiency of the electrode degradation of phenol was explored by a combination of high performance liquid chromatography (HPLC), total organic carbon (TOC) detector and chemical oxygen demand (COD) digestion device. Results show that the electrochemical reaction of phenol on Ti/IrO₂-Ta₂O₅ electrode mainly occurs in the oxygen evolution reaction zone, whereas a small amount of irreversible direct electrochemical oxidation reaction happens at higher concentration of phenol. The larger oxidation peak current and higher charge efficiency are obtained when the concentration of support electrolyte is 5 g·L^-1 and the initial concentration of phenol is 100 mg·L^-1. Under the suitable operating conditions of initial phenol concentration of 100 mg·L^-1, electrolyte concentration of 5 g·L^-1, reaction time of 120 min and current of 40 mA, the removal rate of phenol,COD,TOC and average current efficiency (ACE) can reach 82%,49%,39% and 24.5%, respectively.