R Fadaye Diznab - Chemistry Department, Science Faculty, Islamic Azad University, Aharhar Branch, Ahar, Iran
P Alizadeh Eslami - Applied Chemistry Department, Science Faculty, Islamic Azad University, Tabriz Branch, Tabriz, Iran
P Gharbani - Chemistry Department, Science Faculty, Islamic Azad University, Aharhar Branch, Ahar, Iran

The presence of heavy metals in wastewater and surface water is becoming a severe environmental and public health problem. This study investigated the applicability of α-Fe2O3 and Fe3O4 nanoparticles for the selective removal of chromium from leather tanning wastewater. The size of α-Fe2O3 and Fe3O4 nanoparticles were used are 20~40 nm and 20~30 nm, respectively. The surface area of the α-Fe2O3 and iron oxide (III) nanoparticles were determined to be 40~60 m2/g using the Brunauer–Emmett–Teller method. These experiments were carried out with waste water of the leather tanning by 0.1gr/Lit of both of the iron oxide nanoparticles in a variety of pH from 4 to 12. The amount of chromium was measured by Atomic Absorption Spectrometer. The results show that the 99.94% of chromium was reduced by α-Fe2O3 and 99.96% of chromium was removed by Fe3O4 . The results also show that the adsorption of chromium is independent on the pH.

leather tanning wastewater, magnetic nanoparticles, α-Fe2O3, Fe3O4 , Chromium removal.E-mail: R.Diznab@yahoo.com