Kinetic investigation of the oxidative decolorization of Direct Green 28 and Direct Blue 78 by hydrogen peroxide

This study provides evidence that there is only but one fingerprint acquired by the reaction of each dye from its beginning at t → 0 passing by the uncatalyzed and autocatalyzed stages. The kinetic and activation parameters of the oxidative decolorization of I and II were deduced. The oxidation reaction of both dyes was entropy controlled. A reaction mechanism of the oxidation of each dye was proposed.