Effect of Cd Sorption on the Electrical Properties of Fly Ash

Abstract

The measurement of electrical properties could be a good solution to monitoring the contaminant transport through a barrier. In order to verify the effect of heavy metal sorption on the electrical properties of fly ash, the electrical properties of fly ash contaminated by cadmium based on the permittivity and the electrical resistivity were investigated. Permittivity of fly ash was found to be an inadequate indicator in monitoring the adsorption of cadmium on fly ash. However, in case of Cd-adsorbed fly ash, electrical resistivity was found to be unaffected by cadmium content, giving a relatively consistent value which was significantly greater than that of washed fly ash with contaminated pore water. Therefore, presence of cadmium in the pore water and in the adsorbed state brings about diverging values of electrical resistivity, which may be a good indicator to represent the degree of phase transition of cadmium ions during adsorption by fly ash.roperties of fly ash contaminated by cadmium based on the permittivity and the electrical resistivity were investigated. Permittivity of fly ash was found to be an inadequate indicator in monitoring the adsorption of cadmium on fly ash. However, in case of Cd-adsorbed fly ash, electrical resistivity was found to be unaffected by cadmium content, giving a relatively consistent value which was significantly greater than that of washed fly ash with contaminated pore water. Therefore, presence of cadmium in the pore water and in the adsorbed state brings about diverging values of electrical resistivity, which may be a good indicator to represent the degree of phase transition of cadmium ions during adsorption by fly ash.