Decolourization of azodye solutions by Fentonʹs oxidation

The reaction of azodye active yellow lightfast 2 KT (AYL) with H2O2/Fe2+ system (Fentonʹs reagent) causes a drop in colourization by 95–97% at the minimum dosage of 17 mg•l−1 H2O2. Intensification of the decolourization process is achieved under the influence of solar radiation or an increase in reaction temperature. The effectiveness of hydrogen peroxide action, characterized by the relation Δ[H2O2] / Δ[dye], depends upon its initial concentration. It has been suggested that during the reaction catalyst activity is reduced.