Iron-catalyzed Internal Electrolysis for Pretreatment of Dyeing Intermediate Wastewater

The effect of iron-catalyzed internal electrolysis in pretreatment of dyeing intermediate wastewater was studied,and the influence of initial pH,aeration time,iron dosage,reaction time and so on was investigated.The optimal pretreatment conditions are as follows: pH is 4,aeration time is 3 h,iron dosage is 100 g/L,and reaction time is 30 to 60 min.Under those conditions,COD is reduced from 5 047 mg/L to 2 094 mg/L,its removal rate being 58.51%,and color is reduced from 6 832 times to 747 times,its removal rate being 89.07%.