低浓度NaCl溶液Ti/Pt阳极电解制备活性氯

Investigation on Electrogenerated Active Chlorine from diluted NaCl Solutions at Ti/Pt Anode

以Ti板阴极、Ti/Pt阳极组成无隔膜电解装置,电解低浓度NaCl溶液制得活性氯.研究电解时间、电流密度、氯离子浓度、溶液pH值对活性氯浓度及电流效率的影响.结果表明:电解时间增加,活性氯浓度增加,而电流效率逐渐降低;初始阶段活性氯浓度增加较快,近1 h活性氯浓度趋于稳定;增加氯化钠浓度可提高活性氯浓度和改善电流效率;微酸性电解液有利于提高活性氯浓度.电解过程中,溶液电导率不断降低,pH值变化范围在1之内.

Electrogeneration of active chlorine from diluted NaC1 solutions was investigated in an undivided cell with Ti/Pt anode and Ti plate cathode. The effects of electrolysis time, current density （ i）, chloride concentration and pH value on the clectrogeneration of active chlorine and current efficiency （CE） were analyzed. Meanwhile, the changing trends of the electrolyte＇ s conductivity （TSD） and pH value in the electrolysis process were discussed. The results showed that the concentration of active chlorine increased with electrolysis time, but the trend became slow. During this process, the current efficiency reduced steadily. When i was 4.93 - 7.39 mA/ cm^2, the concentration of active chlorine increased with the increase of i, but no longer increased when the i exceeded 7.39 mA/cm^2. The concentration of active chlorine and CE increased with the increase of NaCl concentration, but the increased range reduced. Acidic electrolyte was beneficial to electrogeneration of active chlorine. During the electrolysis, the TSD decreased steadily and the change of pH value did not exceeded 1.