Photodegradation of Polyphenols and Aromatic Amines in Olive Mill Effluents with Ni Doped C/TiO2

Abstract

Magnetic nickel coated carbon based titanium dioxide [C/TiO2/Ni] nanocomposites were used for photodegradation of polyphenols and total aromatic amines (TAAs) metabolites from olive mill wastewaters (OMW) at different operational conditions such as different mass ratios of C, TiO2, and Ni (1%/2%/5%; 5%/1%/2%; and 2%/5%/1%), being at increasing photodegradation times (15, 30, 45, 60, 75, 120, and 180 min), photocatalyst concentrations (100, 250, 500, and 1000 mg L−1), pH values (3.5, 4.0, 7.0, and 10.0) and temperatures (15°C, 25°C, 50°C, and 80°C), and being under 300 W ultraviolet (UV) and 30 W sunlight irradiation. Under the optimized conditions, at pH=7.0, at 500 mg L−1 C/TiO2/Ni nanocomposite, under 300 W UV light, after 60 min, at 25°C, the maximum CODdissolved, total phenol, and TAAs removals were 99%, 90%, and 96%, respectively. Photodegradation removals in the OMW under sunlight and being lower than those under UV light.