The adsorption of cadmium by goethite and manganite under alkaline conditions

Abstract：The adsorption of cadmium by goethite and manganite was experimentally studied. The adsorption quantity of cadmium by goethite and manganite increased with the increase of pH from acid to neutral and reached the maximum under the alkaline condition. After the adsorption of cadmium by goethite and manganite happened, the pH values of the solutions were changed, and the critical pH values were 8 for goethite and 6.5 for manganite. The adsorption balance time of goethite and manganite for cadmium was 6 hours. The adsorption isotherms were consistent with Freundlich isothermal equation. The adsorption effect of goethite and manganite for cadmium was ideal at the room temperature.