HW型高分子捕集剂处理含铅铜废水

Treatment of Wastewater Containing Pb^(2+) and Cu^(2+) Using HW Polymer Capturing Agent

采用聚丙烯酰胺、NH2OH.HCl和NaOH反应合成了HW型高分子捕集剂(简称捕集剂),考察了捕集剂对Pb2+,Cu2+质量浓度分别为100mg/L的废水的处理效果。研究结果表明:在含Pb2+废水pH为6.5~7.0、n(捕集剂)∶n(Pb2+)=1.6、反应时间为50min的最佳条件下,Pb2+去除率达100.00%;在含Cu2+废水pH为5.5~6.0、n(捕集剂)∶n(Cu2+)=1.0、反应时间为60min的最佳条件下,Cu2+去除率达99.73%。对Pb2+,Cu2+质量浓度分别为50mg/L的混合废水,n(捕集剂)∶n(Pb2++Cu2+)=1.2时,对Pb2+,Cu2+的去除率均达到99%以上。捕集剂去除Pb2+,Cu2+的机理为羟肟酸基团与Pb2+,Cu2+反应生成稳定的螯合物。与中和法沉淀物相比,捕集剂与Pb2+,Cu2+反应生成的螯合物的Pb2+,Cu2+浸出量小,具有更好的环境安全性。

HW polymer capturing agent was synthesized from polyacrylamide, NH2OH · HCl and NaOH and its effects on treatment of wastewaters with 100 mg/L of Pb^2＋ or Cu^2＋ were studied. For the Pb^2＋ -containing wastewater, the removal rate of Pb2＋ is 100% under the optimum conditions of wastewater pH 6.5 - 7.0, n （ capturing agent） ： n （ Pb^2＋ ） = 1.6 and reaction time 50 min; For the Cu^2＋ - containing wastewater, the removal rate of Cu^2＋ is 99. 73% under the optimum conditions of wastewater pH 5.5 - 6.0, n （ capturing agent） ： n （ Cu^2＋ ） = 1.0, and reaction time 60 min. For the mixed wastewater with 50 mg/L of Pb^2＋ and 50 mg/L Cu^2＋, the removal rates of Pb^2＋ and Cu^2＋ can reach above 99% when n（ capturing agent） ： n（ Pb^2＋ Cu^2＋ ） = 1.2. The removal mechanism of Pb^2＋ and Cu^2＋ by the capturing agent is that hydroximic acid group reacts with Pb^2＋ and Cu^2＋ to form stable chelates. Comparing with neutralization precipitates, the chelates are safer for environment with less leaching amount of Pb^2＋ and Cu^2＋,