Abstract:

In this study, the Fenton process and nanofiltration were used to purify wastewater from dyeing with reactive dyes. Ferrous sulfate doses ranging from 100 to 1000 mg/dm³ and hydrogen peroxide doses ranging from 2.5 to 10 cm³/dm³ were applied. It was found that in the whole range of ferrous sulfate doses, the degree of decolorisation was very high, reaching 97- 99%. Consequently the wastewater from the Fenton process was practically completely decolorised. In the case of COD, with increasing doses of ferrous sulfate, the reduction rate initially increased from 25 to 38% and then decreased to 28%. An increase in the hydrogen peroxide dose resulted in a rise in COD reduction to about 50%. It was found that application of the Fenton reaction before the nanofiltration process improved filtration parameters. A clear reduction in the fouling effect of the membrane in the integrated wastewater treatment process was reported as compared to nanofiltration alone.