The Potential of Fe-exchanged Y Zeolite as a Heterogeneous Fenton-type Catalyst for Oxidative Degradation of Reactive Dye in Water

The study aimed to investigate the potential of Fe-exchanged zeolites of Y-type as a catalyst in heterogeneous Fenton-type processes for the degradation of model organic pollutant, reactive azo dye C.I. Reactive Blue 137, in water. The research work was directed to investigate the influence of process variables, such as FeY catalyst dosage, Fenton reagent ratio, and initial operating pH on the efficiency of the treatment process. The performance of the studied heterogeneous process was compared with corresponding homogeneous Fenton-type processes, while the influence of UV light on both heterogeneous and homogeneous processes was investigated as well. The results of FeY catalyst characterization indicate that the iron content is mainly built into the inner zeolite micropores providing the benefit to zeolite stability and activity of the catalyst. Based on the decolorization and the mineralization degree of RB137 model wastewater, the overall process efficiency was estimated. Homogeneous and heterogeneous Fenton processes yielded similar decolorization and mineralization, but the concentration of Fe ions in the bulk after treatment was significantly lower in the latter case. Moreover, the use of the heterogeneous catalyst allowed the UV-assisted process to be operated at milder pH conditions, pH 5, while the most suitable pH for the dark heterogeneous process showed to be pH 3