Catalytic ozonation of reactive red 195 azo dye

Reactive azo dyes are widely used in textile industry. Due to their toxicity and recalcitrance, these dyes can be hazardous to the environment and resistant to destruction by biological treatment methods. Catalytic ozonation is an innovative advanced oxidation process (AOP) and involves the generation of hydroxyl radicals which are higher electrochemical oxidation potential compared with molecular ozone. In this study ozone, ozone/ granular activated carbon (GAC) and ozone/Mn loaded GAC processes were used in order to remove dye and total organic carbon (TOC) of the reactive red 195 azo dye. The mineralization of the solutions was followed by measuring the total organic carbon. The effect of pH and t-butanol on the ozon/GAC process was searched. pH 11, 100 mg/L dye concentration and 1,0 g/L GAC amount were determined as optimum conditions. Consequently active carbon accelerated the reaction of ozonation, thus the efficiency of applied process was enhanced. Keywords: Ozone, reactive red 195, catalytic ozonation, granular activated carbon (GAC), advanced oxidation processes.