To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer ...To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer program Pollute V6.3, the effective diffusion coefficients of K^＋ of the soils were back-calculated from the diffusion tests. It is found that the Ariake clay has a larger effective diffusion coefficient than the Akaboku soil, indicating that the Ariake clay may provide a better diffusion barrier. A comparison of the effective diffusion coefficients between the single-salt solution condition and the multi-salt solution condition indicates that soils have higher effective diffusion coefficients under the former condition. It is suggested to use miscible solution close to landfill leachates for determining effective diffusion coefficients of specified chemical species for a practical design.展开更多
Effects of organic acids (oxalic, acetic, and citric) on adsorption characteristics of Cadmium (Cd) on soil clay minerals (kaolinite, goethite, and bayerite) were studied under different concentrations and different p...Effects of organic acids (oxalic, acetic, and citric) on adsorption characteristics of Cadmium (Cd) on soil clay minerals (kaolinite, goethite, and bayerite) were studied under different concentrations and different pH values. Although the types of organic acids and minerals were different, the effects of the organic acids on the adsorption of Cd on the minerals were similar, i.e., the amount of adsorbed Cd with an initial solution pH of 5.0 and initial Cd concentration of 35 mg L-1 increased with increasing concentration of the organic acid in solution at lower concentrations, and decreased at higher concentrations. The percentage of Cd adsorbed on the minerals in the presence of the organic acids increased considerably with increasing pH of the solution. Meanwhile, different Cd adsorption in the presence of the organic acids, due to different properties on both organic acids and clay minerals, on kaolinite, goethite, or bayerite for different pHs or organic acid concentrations was found.展开更多
文摘To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer program Pollute V6.3, the effective diffusion coefficients of K^＋ of the soils were back-calculated from the diffusion tests. It is found that the Ariake clay has a larger effective diffusion coefficient than the Akaboku soil, indicating that the Ariake clay may provide a better diffusion barrier. A comparison of the effective diffusion coefficients between the single-salt solution condition and the multi-salt solution condition indicates that soils have higher effective diffusion coefficients under the former condition. It is suggested to use miscible solution close to landfill leachates for determining effective diffusion coefficients of specified chemical species for a practical design.
基金Supported by the National Key Basic Research Support Foundation of China (No. 2002CB410804) the National Natural Science Foundation of China (No. 40201026).
文摘Effects of organic acids (oxalic, acetic, and citric) on adsorption characteristics of Cadmium (Cd) on soil clay minerals (kaolinite, goethite, and bayerite) were studied under different concentrations and different pH values. Although the types of organic acids and minerals were different, the effects of the organic acids on the adsorption of Cd on the minerals were similar, i.e., the amount of adsorbed Cd with an initial solution pH of 5.0 and initial Cd concentration of 35 mg L-1 increased with increasing concentration of the organic acid in solution at lower concentrations, and decreased at higher concentrations. The percentage of Cd adsorbed on the minerals in the presence of the organic acids increased considerably with increasing pH of the solution. Meanwhile, different Cd adsorption in the presence of the organic acids, due to different properties on both organic acids and clay minerals, on kaolinite, goethite, or bayerite for different pHs or organic acid concentrations was found.
