Performance Evaluation of Fenton Oxidation Treatment Method for the Reuse of Reactive Dyeing Effluent

Abstract

In this study, a novel wash-off method was investigated wherein the use of Fenton’s reagent was evaluated to get rid of hydrolyzed and unfixed reactive dyes from wash-off liquor and reused in next wash-off process. After dark shade dyeing (5% o.w.f) with C.I. Reactive Blue 72, C.I. Reactive Blue 221, C.I. Reactive Red 141, C.I. Reactive Red 198, C.I. Reactive Orange 84, C.I. Reactive Orange 122, C.I. Reactive Yellow 105 and C.I. Reactive Yellow 138 , fabrics were subjected to both clean water (reference) and treated wash-off liquors (batch) and comparisons were made. Fenton reagent was proved capable to achieve 88-97% color reduction in wash-off liquor at pH 3 by using optimal dose of FeSO4 and H2O2 at room temperature. Then effectiveness of Fenton’s reagent treated wash-off was evaluated in terms of color difference values (ΔL*, ΔC*, Δh* and ΔE*), wash fastness and crocking properties. For color fastness properties the commercially tolerable value of ΔE*≤1 was observed for blue and red dyes and slightly higher value for yellow and orange dyes. Wash fastness and crocking results are almost similar for reference and batch dyed fabrics and their values ranges 4-5 on grey scale. Color strength (K/S) showed negligible difference in values indicating that fabrics absorbed almost same amount of dyestuff for each dye .Fenton method of treatment proved to be an eco-friendly and economically feasible treatment method and treated liquor can be effectively used in next dyeing, without compromising quality parameters.