Adsorption of Cd(II) by dried activated sludge

The biosorption of Cd(II) ions from aqueous solutions by dried activated sludge was investigated as a function of initial pH, initial cadmium ion concentration, adsorbent mass, adsorbent particle size and temperature. Biosorption experiments were performed using activated sludge of the systems of wastewater refining of milk factory.The results showed that The maximum adsorption capacity of the sludge increased as the temperature increased. Increasing the adsorbent particle sizes and the initial cadmium ion concentration decreased the removal efficiency, but Increasing the initial pH and the adsorbent mass increased the removal efficiency. The equilibrium data fitted very well to both Langmuir and Freundlich adsorption models.

Keywords:

Biosorption , Adsorption isotherm , Heavy metal , Activated sludge , Industrial wastewater