Study on the Effect of Carboxyl Bagasse Hemicellulose on Heavy Metal Adsorption

In this paper, ions i.e. Cu2+, Pb2+and Cd2+ were absorbed by the carboxyl bagasse hemicelluloses, and the influences of pH value, adsorption time and the initial concentration of metal ion have been studied. The results show that the optimal adsorption pH values for Cu2+, Pb2+and Cd2+ are 5.5, 5.5 and 7.5, respectively. The adsorption capacity to ions Cu2+, Pb2+and Cd2+ reaches the maximum values when the adsorption time is 180 min. Net adsorption to ions Cu2+, Pb2+and Cd2+ increases with increasing the initial concentration of the metal ions. Analysis results of adsorption dynamics show that the adsorption of Cu2+, Pb2+and Cd2+ follows Ho 's Pseudo second-order kinetics linear model. It can be seen from the adsorption isothermal research that absorption of the carboxyl bagasse hemicelluloses to ions Cu2+, Pb2+and Cd2+ can be well described by the Langmuir isotherm linear model. Moreover, the theoretical values of the maximum absorption capacity qmax for ions Cu2+, Pb2+and Cd2+ were determined to be 20.28 mg/g, 82.64 mg/g and 30.58 mg/g, respectively.