Effects of co-ion initial concentration ratio on removal of Pb2+ from aqueous solution by modified sugarcane bagasse

A modified sugarcane bagasse (SCB) fixed bed column was used to remove Pb2+ from aqueous solution. To determine the optimal condition for Pb2+ separation, Ca2+ was chosen as the model interfering ion, and effects of Ca2+ and Pb2+ initial concentration ratio (C-0(Ca) : C-0(Pb)) on the adsorption of Pb2+ were investigated. Results showed that adsorption amount ratio of Ca2+ and Pb2+ (q(e)(Ca) : q(e)(Pb)) had a good linear relationship with C-0(Ca) : C-0(Pb). Mass ratio of Pb2+ absorbed on the modified SCB was higher than 95% at C-0(Ca) : C-0(Pb) < 1.95, illustrating that Pb2+ could be selectively removed from aqueous solution. To verify that, simulated waste water containing co-ions of K+, Na+, Cd2+ and Ca2+ was treated, and results showed that the equilibrium amount of Pb2+, K+, Na+, Cd2+ and Ca2+ adsorbed was 134.14, 0.083, 0.058, 1.28, and 1.28mg g(-1), respectively, demonstrating that the modified SCB could be used to remove Pb2+ from aqueous solution in the investigated range.