高级氧化法破络处理柠檬酸铜镍电镀废水

Complex Breakdown Treatment for Copper-Nickel Citrate Electroplating Wastewater by Advanced Oxidation Process(AOP)

以柠檬酸单独络合铜离子、柠檬酸单独络合镍离子、柠檬酸综合络合铜镍离子这3种模拟电镀废水为对象,采用芬顿(Fenton)、高锰酸钾(KMnO_4)以及过硫酸钠(Na_2S_2O_8)三种氧化法进行氧化破络,并结合加碱沉淀工艺对铜镍离子进行去除。结果表明,Fenton氧化法最佳反应参数:初始pH值为3.0,Fe^(2+):H_2O_2摩尔比为1:10,30%H_2O_2投加量为0.05 mL/L,反应时间为30 min。KMnO_4氧化法最佳反应参数:初始pH值为3.0～4.0,KMnO_4投加量为37.5 mg/L,反应时间为80 min。Na_2S_2O_8氧化法最佳反应参数:温度为20℃,初始pH值为2～7,S_2O_8^(2-):Fe^(2+)摩尔比为1:1,Na_2S_2O_8投加量为0.1 g/L,反应时间为90 min。对比三种氧化法,可以得出,对pH的适应性:Na_2S_2O_8氧化法>KMnO_4氧化法>Fenton氧化法;氧化效率:Fenton氧化法>KMnO_4氧化法>Na_2S_2O_8氧化法;经济效率:KMnO_4氧化法>Na_2S_2O_8氧化法>Fenton氧化法。因此,对于不同的废水,根据其特点选择合适的处理方法是十分必要的。

Three oxidation methods,namely Fenton,KMnO 4 and Na2S2O8,were studied for the complex breakdown treatment of synthetic electroplating wastewater containing citric acid complex copper ion,citric acid complex nickel ion,and combined citric acid complex copper and nickel ions.The treatment was carried out with alkali precipitation process.The optimum parameters of Fenton oxidation process were as follows:initial pH value was 3.0,molar ratio of Fe^2+∶H2O2 was 1∶10,dosage of 30% H2O2 was 0.5 mL/L,reaction time was 30 min.The optimum parameters of KMnO4 oxidation method were as follows:initial pH value was 3.0~4.0,dosage of KMnO4 was 37.5 mg/L,reaction time was 80 min.The optimum parameters of Na2S2O8 oxidation method were as follows:temperature was 20 ℃,initial pH value was 2~7,molar ratio of S2O8^2-∶Fe^2+ was 1∶1,dosage of sodium persulfate was 0.1g/L,reaction time was 90 min.Comparing the three oxidation methods,results showed that the order for the adaptability of pH was Na2S2O8> KMnO4>Fenton,the order for the oxidatio efficiency was Fenton>KMnO4>Na2S2O8,and the order for the economic efficiency was KMnO4>Na2S2O8>Fenton.Therefore,for different wastewater,selecting the appropriate treatment method in accordance with its characteristics is very necessary.