ACF电极电解处理含NaCl结晶紫染料废水的研究

Study on electrochemical treatment of crystal violet dye wastewater in NaCl medium with ACF electrode

以吸附结晶紫达到饱和的活性炭纤维为阳极,在NaCl介质中对初始浓度为100 mg/L的结晶紫染料废水进行了电解脱色处理。实验考察了NaCl浓度、pH值和电流密度等对溶液脱色率的影响,测定了电解时溶液中生成的游离氯浓度及不同电解时间后溶液的紫外-可见吸收光谱曲线,并对不同电解时间后溶液的归一化吸光度比值进行了计算。结果发现,溶液中所产生的游离氯的浓度随电解时间的增加快速上升,20 min时就几乎达到了最大值;在活性氯的作用下,结晶紫分子中的大π共轭体系被破坏,溶液迅速脱色;电解液中所含的NaCl浓度、电解液的pH值和电流密度等都对脱色率有影响;在一定实验条件下,初始浓度为100 mg/L的结晶紫染料废水在电解60 min后脱色率可高达99.3%。

The electrochemical treatment of dye wastewater with initial concentration of 100 mg/L crystal violet was performed by using an activated carbon fiber（ACF） as an anode in NaCl medium.Before the treatment,the ACF was immersed in crystal violet solution until saturated adsorption.The influence of NaCl concentration,initial pH and current density on the decoloration rate was investigated.The concentration of dissociative chlorine generated in electrolyte was determined.UV-vis spectra of original solution and the treated solutions at different electrolysis time were also measured.The ratios of normalized absorbance at different electrolysis times were calculated.The experimental results indicated that the concentration of dissociative chlorine generated in electrolyte increased rapidly with electrolysis time and almost reached the maximum at 20 min.The big π bond conjugate system of crystal violet was destroyed under the action of dissociative chlorine,so dye wastewater was decolored rapidly.NaCl concentration,initial pH and current density all influenced the decoloration rate of dye wastewater.Under certain conditions,the decoloration rate of dye wastewater with initial concentration of 100 mg/L crystal violet could be up to 99.3% after 60 min of electrolysis.