Activated carbon catalyzed ozonation (ACCO) of Reactive Blue 194 azo dye in aqueous saline solution: Experimental parameters, kinetic and analysis of activated carbon properties

Comparative study of Reactive Blue 194 (RB194) degradation using activated carbon catalyzed ozonation (ACCO) as a hydroxyl radical-based advanced oxidation processes (HO.-AOPs) and single ozonation (O-3) processes was investigated in this study. Furthermore, the effect of chloride ion (Cl- ) on the dye reduction and mineralization was evaluated at different pH values. ACCO was more successful in the reduction of UV254 absorbance and chemical oxygen demand (COD) removal. In ACCO, the dye reduction was marginally increased with adding NaCl concentration from 5 to 50 g/L; while in O-3 process, no significant differences were found. In ACCO, higher dye removal rate could be attributed to the production of reactive chlorine species. The results exhibited that temperature elevation promoted color, aromaticity, and COD removal in the ACCO process. Regeneration of activated carbon by ozone modified surface characterization through addition of acidic oxygen groups. In summary, the ACCO process can be suggested as a promising technology for dye removal from saline industrial wastewaters.