Photocatalytic degradation of textile dyeing wastewater through microwave synthesized Zr-AC, Ni-AC and Zn-AC

The novel zirconium oxide, nickel oxide and zinc oxide nanoparticles supported activated carbons (Zr-AC, Ni-AC, Zn-AC) were successfully fabricated through microwave irradiation method. The synthesized nanoparticles were characterized using XRD, HR-SEM, XPS and BET. The optical properties of Zr-AC, Ni-AC and Zn-AC composites were investigated using UV-Vis diffuse reflectance spectroscopy. The photocatalytic efficiency was verified in the degradation of textile dyeing wastewater (TDW) in UV light irradiation. The chemical oxygen demand (COD) of TDW was observed at regular intervals to calculate the removal rate of COD. Zn-AC composites showed impressive photocatalytic enrichment, which can be ascribed to the enhanced absorbance in the UV light region, the effective adsorptive capacity to dye molecules, the assisted charge transfer and the inhibited recombination of electron-hole pairs. The maximum TDW degradation (82% COD removal) was achieved with Zn-AC. A possible synergy mechanism on the surface of Zn-AC was also designed. Zn-AC could be reused five times without exceptional loss of its activity.