摘要：

为了高效、低成本地处理含Cr(Ⅵ)废水,提出采用离子交换-还原沉淀耦合工艺处理该废水。结果表明,将质量浓度为100 mg/L的含Cr(Ⅵ)废水以20 mL/min连续10.5 h流经离子交换柱,Cr(Ⅵ)的吸附率高达99.9%;用5%NaOH溶液洗脱饱和的离子交换树脂,洗脱液含Cr(Ⅵ)高达6 918.7 mg/L。FeSO₄.7H₂O还原处理浓缩后的高浓度含Cr(Ⅵ)废水的最佳反应条件为pH≥7,反应时间30 min,搅拌速度100 r/min,FeSO₄.7H₂O投加量为理论投加量的1.2倍,此条件下Cr(Ⅵ)去除率高达99.7%。

关键词: 含Cr(Ⅵ)废水, 离子交换树脂法, FeSO₄.7H₂O, 还原沉淀法

Abstract:

The coupling process of ion-exchange-reduction precipitation,has been carried out for treating the wastewater containing Cr(Ⅵ) with high efficiency and low cost. The results show that when the Cr(Ⅵ)-containing wastewater，whose mass concentration is 100 mg/L，is used for flowing through the ion exchange column continuously for 10.5 h，with 20 mL/min，the adsorbing rate of Cr (Ⅵ) is as high as 99.9%. 5% NaOH solution is used for eluting the saturated ion exchange resin. The Cr (Ⅵ ) contained in eluting liquid is as high as 6 918.7 mg/L. After the Cr(Ⅵ)-containing wastewater with high concentration is treated by FeSO₄·7H₂O reduction process. Under the following optimum reaction conditions：pH ≥7，reaction time 30 min，stirring speed 100 r/min，and dosage of FeSO₄·7H₂O 1.2 times of the theoretical amount，its Cr(Ⅵ) removing rate can be up to 99.7%.

Key words: wastewater containing Cr(Ⅵ), ion exchange resin method, ferrous sulfate, reduction precipitation process

中图分类号: 

• TQ09

• X703.1