Inquest of efficient photo-assist advanced oxidation processes (AOPs) for removal of azo dye (acid yellow 17) in aqueous medium: a comprehensive study on oxidative decomposition of AY 17

In this study, the photo-assist degradation of acid yellow (AY 17) dye is reported in detail by applying various UV radiation supported advanced oxidation processes (AOPs). The AY 17 dye in water solution (model and natural) is decomposed by direct photolysis, UV/oxidant, photo-Fenton, photo-Fenton-like, UV/HSO 5 – /Fe 2+ , and UV/S 2 O 8 2− /Fe 2+ system. All applied processes are found to be the comparably effective at pH 3.0. It is observed that the efficiency of AY 17 degradation increased with the initial concentration of the oxidants (H 2 O 2 , HSO 5 – and S 2 O 8 2– ) and catalyst (Fe 2+ and Fe 3+ ). Moreover, the initial concentration of the dye solution has inverse effect on the efficiency of applied AOPs. It is also reported that decomposition of dye through photo-assist AOPs followed pseudo-first-order kinetic while the efficiency of all processes increased with temperature. The activation energy ( E a ) has been determined in the range of between 10 to 20 kJ/mol. The entropy of degradation is also calculated and has found to be positive. Finally, it is concluded that photo-Fenton process (UV/H 2 O 2 /Fe 2+ ) is comparably more efficient method for the removal of AY 17 dye from natural water sample.