Azo dyes commonly used in various industries have a stable and toxic structure. Wastewater containing AY17 dye as a model contaminant was investigated in terms of color and COD removal by both adsorption and persulfate oxidation activated with the PAC. In this study, the effects of temperature (25-50 °C), pH (3-10), persulfate concentration (1000-4000 mg/L), adsorbent dosage (0.1-0.5 g), reaction time (5-60 min), dye concentration (300-1000 mg/L) and NaCI concentration (0-1000 mg/L) on both color and COD removals from wastewater containing AY17 dye were examined. As a result of the study, it was seen that the dosage of adsorbent, pH and reaction time are important parameters in both systems. The use of the PAC as an adsorbent caused to shortening of the reaction time in the HPS system. It also showed that acidic and neutral pH values are more suitable for the removal of AY17 with both systems. Color and COD removal were determined as 100-88.4% and 100-96.6%, respectively, at optimum values obtained for the adsorption and HPS system. An experimental design was applied for various operating parameters in order to analyze experimental data. Models have been proposed for both color removal and COD removal estimates for both systems.
Keywords: Adsorption; Heterogeneous persulfate oxidation; Powder activate carbon; Salt; Temperature; pH.
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