Removal of chemical oxygen demand from industrial estate sewage over hybridized anatase-graphene oxide-carbon nanotubes nanocomposite under solar irradiation

Abstract

The aim of present work was to investigate the performance of hybridized materials, containing anatase, graphene oxide (GO), and carbon nanotubes (CNTs) in the photocatalytic treatment of sewages discharged from the industrial estate. The obtained results demonstrated the ability of hybridized nanocomposite for the solar treatment of sewages collected from different stages of industrial recovery process, between upstream of anaerobic system, and downstream of sand filter. The appropriate proportions of GO, and CNTs were determined, as 3.33 %. The effects of variables like initial COD, irradiation time, sewage collection position, and pH were evaluated on the treatment performance. If the initial COD is controlled at the level of 780 mg.l−1, the COD removal efficiency reaches to ∼90 % which is the prohibitive condition in the industrial scale. The maximal photoactivity was achieved within 20 min by the control of sewage pH at the level of 8. The COD removal kinetics were related to the load of anatase nanoparticles, < 20 nm, specific surface area, 60 m2. g−1, and band gap energy, 2.1 eV, of prepared nanocomposite which is a promising material for the wastewater cleaning in the real condition.