Fenton试剂氧化—絮凝法去除水中As(Ⅲ)

随着地下水砷污染问题的加重,砷污染已成为世界普遍关注的问题。为寻求经济合理的除砷技术,采用Fenton试剂氧化—絮凝法进行了水中As(Ⅲ))的去除试验。当废水初始As(Ⅲ)浓度为0.5 mg/L时,试验确定的最佳除砷条件为,调节废水初始pH=3.0、H_2O_2用量10 mg/L、Fe~(2+)与H_2O_2的摩尔比0.2、反应时间10 min,此时As(Ⅲ)去除率为95.17%。采用此最佳条件对赣州某实际废水进行除砷试验表明,As(Ⅲ))去除率可达94.71%,反应后水中As(Ⅲ))浓度为0.004 2 mg/L,低于《GB5749—2006生活饮用水卫生标准》中0.01 mg/L的标准。Fenton氧化—絮凝法除砷是利用Fenton反应产生的中间产物(包括H_2O_2、·OH、O_2·、·HO_2等)将As(Ⅲ)氧化与铁盐絮凝结合起来的一种方法。

As (Ⅲ) Removal in Water by Fenton Oxidation-Flocculation Method

With the deterioration of groundwater arsenic pollution problem,arsenic pollution has become an issue of common concern in the world.To seek for the economic and reasonable arsenic removal technology,Fenton reagent oxidation-flocculation method is used for As (Ⅲ) removal test.Initial wastewater As (Ⅲ) concentration is 0.5 mg/L,optimum arsenic removal condition ensured in experiment is regulating wastewater initial pH =3.0,H2O2 dosage of 10 mg/L,mole ratio of Fe2+ to H2O2 is 0.2,reaction time is 10 min,As (Ⅲ) removal rate was 95.17％.Adopt the best conditions for a actual arsenic bearing wastewater from Ganzhou removal test showed that the As (Ⅲ)) removal rate can reach 94.71％,As(Ⅲ) concentration in water is 0.0042 mg/L,below the standard of 0.01 mg/L in drinking water health standards (GB5749-2006).Fenton oxidation-flocculation arsenic removal is a method using intermediate (including H2O2,· OH,O2 ·,· HO2,etc.) produced in Fenton reaction to flocculation combined As (Ⅲ) and iron salt.