A NOVEL APPROACH FOR OXIDATIVE DEGRADATION OF SOME ANIONIC AZO DYES BY ALKALINE HEXACYANOFERRATE (III) ION

The degradation of anionic azo dye via Hexacyanoferrate (III) ions (oxidant) in the aqueous alkaline medium has been investigated through kinetic–spectrophotometric technique. The efficiency of this treatment strongly depends on the chemical structure of dyes. The effect on the reaction of various parameters (concentration of dyes, oxidant, and pH solution) has been examined. The degradation of acid red 27, acid yellow 23, and azo violet dyes follow the first-order kinetic model concerning [HCF (III)] and [Dye]. The degradation rates of dyes follow the order: acid red 27> acid yellow 23> azo violet. The successive products of the dyes reveal that the dyes are effectively oxidized via HCF (III) in aqueous alkaline medium. Thermodynamic parameters of acid red 27 dyes at four different temperatures ranging between 40 to 55 ºC reveal that the degradation rate of acid red 27 dye is much better from azo violet, acid yellow 23.