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Azo dyes are extensively used for dyeing textiles, paper, leather and other materials. The industrial wastewater bearing these dyes leads to several environmental and health hazards. Out of the several methods developed to treat industrial wastewater, oxidative decolorization is considered as a simple and economic technology for the removal of azo dyes. Consequently, we have developed optimum conditions for the facile oxidative decolorization of several azo dyes viz p-aminoazobenzene, p-hydroxyazobenzene, eriochromebalck-T, orange-II, ethylorange, acid orange-7, methyl red, amaranth and sunset yellow dyes using organic N-haloamines as oxidants under various experimental conditions. Platinum group metal ions have been employed as homogeneous catalysts for the redox systems studied and the impact of these catalysts has been explored to a large extent. The kinetic study justifies the use of platinum group metal ions facile oxidation of these redox systems. All the kinetic and thermodynamic parameters have been deduced. The kinetic and mechanistic picture of the redox systems investigated have been clarified to a large extent. The intermediate complexes and products have been characterized by spectral data. The values of Chemical Oxygen Demand (COD) were determined. The applicability of these developed methods were tested with wastewater containing azo dyes, which were collected from various dyeing industries and the results obtained were quite satisfactory. Due to the simplicity and cost effectiveness of these methods, they can be adopted to treat industrial wastewater involving azo dyes after suitable experimental modifications. Hence, these developed technologies are valuable additions to the existing methods with several advantages.