DEGRADATION KINETIC OF REACTIVE RED AZO DYE BY FENTON-LIKE PROCESS USING ONLINE SPECTROPHOTOMETRIC METHOD

Online spectrophotometric monitoring technology provides a fast, accurate and convenient method to detect the change of dye concentration in a degradation process. Fenton-like degradation kinetics of reactive red azo dye were investigated using online spectrophotometric technology. The pseudo first order and Behnajady- Modirshahla-Ghanbery (B-M-G) kinetics models were described degradation processes at all the reaction conditions. The results showed that the best degradation rate of reactive red was nearly 100% after 400 s with Fe3+ = 5x10-4 mol.L-1, H2O2=1x10-2 mol.L-1, pH=4 and T = 15 degrees C. The B-M-G kinetics model was better to be followed in dye degradation than pseudo first order. The instantaneous reaction rates and hydroxyl radicals were calculated and reflected some important information at all the conditions based on two kinetics.