New Process for the Treatment of Polluted Water Using the Coupling of Nanoparticles and Magnetic

Abstract

Many of the current strategies for removing pollutants from water are based on nanomaterials and 18nanotechnology. Lower values of Biological Oxygen Demand (BOD5) and Chemical Oxygen De- 19 mand (COD) in water results in reduction in the amount of oxidizable pollutants. We present a study 20 on the reduction of COD and BOD5in water from Wadi El Bey River (Tunisia), using magnetite na- 21 noparticles (MNPs) and magnetic fields. The COD and BOD5 removal reached values higher than 22 50% after 60 min, with optimum efficiency at pH values of ≈8 and for MNPs concentrations of 1 g/L. 23 The use of a permanent magnetic field (0.33 T) showed an increase of COD and BOD5 removal from 2461% to 76% and from 63% to 78%, respectively. This enhancement is discussed in terms of the MNPs 25coagulation induced by the magnetic field and the adsorption of ionic species onto the MNPs sur- 26face due to Fe3O4 affinity.