Valorization of olive stone and sugar cane bagasse by-products as biosorbents for the removal of cadmium from aqueous solution

Olive stone and sugar cane bagasse by-products were used as effective and green biosorbents for the removal of cadmium from aqueous solutions. The efficiency of the biosorbents was characterized by, FTIR, BET, SEM and zeta potential analysis. The effect of pH, initial concentration of Cd2+, contact time and temperature on the adsorption was studied. Both olive stone and bagasse exhibit the highest Cd2+ uptake capacity at a temperature of 298 K and initial pH value of 7. For both biosorbents, the equilibrium uptake increased with increasing metal ion concentration with a maximum removal capacity of 96%. Pseudo-second-order adsorption kinetic model satisfactorily simulates the adsorption behavior of Cd2+. The result shows the high potential of using olive stone and sugar cane bagasse by-products as green and inexpensive biosorbents for the removal of cadmium and for the waste-water treatment. (C) 2014 Elsevier Ltd. All rights reserved.