Copper cable doped with tin oxide and its application to photodegrade natural organic matters

Natural organic matters are of particular importance in drinking water treatment due to their reaction with chlorine, and formation of disinfection byproducts that cause cancer in humans. Photocatalysis can remove natural organic matters from water but usually powdery photocatalysts are used which should be separated from water by filtration due to their toxic effects. In this work, a piece of copper cable used in electric industries was doped with tin oxide and applied as a photocatalyst to remove natural organic matters, humic acid and humate liquid fertilizer, from water. Tin (II) chloride was used as precursor, and deposited on the copper cable by dip coating method. Then the coated cable was calcinated at 300 °C. The prepared SnO₂/CuO/Cu photocatalyst was characterized by ICP, SEM, DRS, XRD, and ASAP techniques. The results of XRD confirmed the existence of copper oxide, and tin oxides. DRS showed that doping with tin oxide caused the photocatalytic property to improve, and the catalyst was active under irradiation of UV-Vis light. Effects of humic acid concentration, photocatalyst length, and time were studied. The kinetic of humic acid photodegradation by the SnO₂/CuO/Cu photocatalyst was investigated, which obeyed the first order model. The photocatalyst regeneration and reuse were investigated in five cycles, and the results indicated that photocatalytic activity was remained nearly constant. The cable form SnO₂/CuO/Cu photocatalyst with the main advantage of easy separation from water without the need to filtration, has excellent photocatalytic activity.