Study on factors of effecting adsorption of Cr 6+ in wastewater by bentonite

The removal of chromium cations from artificial wastewater and actual effluent by Ca-bentonite and Na-exchanged bentonite was studied. The experimental results showed that the equilibrium time of adsorbing chromium cations were 1h. The quantity of adsorption decreases with the increase of initial concentration of chromium cations, pH and adsorption temperature. Na-exchanged bentonite sorbed higher amounts of Cr 6+ than the natural bentonite, the removal rate of Cr 6+ reached to 95%.