Separation of Pb2+ from Mg2+ by modified sugarcane bagasse under batch and column conditions: Effect of initial concentration ratio

Abstract

Effect of initial concentration ratio C0Mg:C0Pb on separation of Pb2+ from Mg2+ by the modified sugarcane bagasse was carried out under batch and column conditions. For comparison, the adsorption performance of the modified SCB (sugarcane bagasse) for Pb2+ in one component system was studied under the two conditions. Amount of Pb2+ and Mg2+ adsorbed on the column in the binary system was calculated through the elution curves. Results showed that the adsorption capacity of Pb2+qePb decreased while that of Mg2+qeMg increases with the increase of C0Mg:C0Pb, and good linear relationships between C0Mg:C0Pb and qeMg/qePb were obtained under both conditions. According to the linear equations, mass ratio of metal ions adsorbed on the modified SCB was calculated. It was observed that mass ratio was higher than 95% for Pb2+ at C0Mg:C0Pb<0.022 while for Mg2+ at C0Mg:C0Pb>10.01 under batch condition. Under the column condition, high mass ratio (>95%) for Pb2+ and Mg2+ was obtained at C0Mg:C0Pb<1.24 and C0Mg:C0Pb>585.5, respectively. The above results showed that modified SCB could be used to separate Pb2+ and Mg2+ when C0Mg:C0Pb<1.24 (Pb2+ adsorbed selectively) or C0Mg:C0Pb>10.01 (Mg2+ adsorbed selectively). These findings would provide theoretical guidance for separation of metal ions.