Removal of Pb2+and Cd2+by adsorption on clay-solidified grouting curtain for waste landfills
来源期刊：中南大学学报(英文版)2006年第2期
论文作者：陈永贵 张可能 邹银生 邓飞跃
文章页码：166 - 170
Key words：adsorption; clay-solidified grouting curtain; Pb2+; Cd2+; Freundlich model; leachate treatment
Abstract: Pb2+and Cd2+ in leachate were adsorbed on clay-solidified grouting curtain for waste landfills with equilibrium experiment. The cation exchange capacity was determined with ammonium acetate. And the concentration of heavy metal cations in leachate was determined with atomic absorption spectrophotometer. Their equilibrium isotherms were measured, and the experimental isotherm data were analyzed by using Freundlich and Langmuir models. The results show that the adsorption capacities of the heavy metal cations are closely related to the compositions of clay-solidified grouting curtain, and the maximum adsorption appears at the ratio of cement to clay of 2∶4 in the experimental conditions. At their maximum adsorption and pH 5.0, the adsorption capacities of Pb2+ and Cd2+ are 16.19 mg/g and 1.21 mg/g. The competitive adsorption coefficients indicate that the adsorption of clay-solidified grouting curtain for Pb2+ is stronger than that for Cd2+. The adsorption process conforms to Freundlich s model with related coefficient higher than 0.996.
