Photoassisted Fenton degradation of phthalocyanine dyes from wastewater of printing industry using Fe(II)/γ-Al2O3 catalyst in up-flow fluidized-bed

Fe(II)/γ-Al2O3 powders synthesized using the dipping method were produced from a mixed aqueous solution containing aluminium oxide (γ-Al2O3) and iron(II)-precursor (FeSO4), and used for photo-Fenton degradation of phthalocyanine dyes (PCS) under ultraviolet (UV) irradiation in an up-flow fluidized bed. The catalysts were characterized by XRD, ESCA, BET, EDS and SEM. The results showed that Fe2+ ion was compounded on the γ-Al2O3 carrier. The effects of different reaction parameters such as catalyst activity, dosage and solution pH on the decolorization of PCS were assessed. Results indicated that maximum decolorization (more than 95%) of PCS occurred with 20 wt% Fe(II)/γ-Al2O3 catalyst (dosage of 60 g/L) using a combination of UV irradiation and heterogeneous Fenton system. The degradation efficiency of PCS increases as pH decreases, exhibiting a maximum efficiency at pH 3.5. The recycled catalyst was capable of repeating three runs without a significant decrease in treatment efficiency, and this demonstrated the stability and reusability of catalyst.