| Soil pollution is lagging, dormant and irreversible, therefore, soil pollution is usually difficult to be remedied and treated. Heavy metal is a kind of important soil pollutant. This paper reviewed the soil remediation technology firstly, used cadmium as a representative heavy metal pollutant, investigated the effect of different factors on desorptions of cadmium, and investigated the electrikinetic movement of cadmium with different conditions. The feasibility of the process to restore Cd-comtaminated soil by an iron (Fe) and carbon (C) primary cell is studied also. The main conclusions of this thesis are as follows:(1) The desorption of cadmium increased with the decline of pH and the increase of ionic strength. At pH below 4.8, the desorption of cadmium declinced linearly with the rise of pH. The desorption of cadmium can enhanced by organic acids. EDTA showed excellent enhancement on the desorption of cadmium, however, the desorption of cadmium can not be enhanced by citric acid.(2) In the process to restore Cd-comtaminated soil by electrikinetic, the movement of cadmium was greatly increased with the rise of the electric potential. The movement of cadmium was also related to the value of pH. Low pH also has enhancement on the elecromigration efficiency of cadmium.(3) The processes to restore Cd-comtaminated soil by an iron (Fe) and carbon (C) primary cell were feasible. A primary cell, with different distances of electrodes, 10 cm, 20 cm, 30 cm and 50 cm respectively, were used to restore Cd-comtaminated soil. The results indicated that the eletromigration efficiencies of Cd declined with the increase of distance. And the eletromigration efficiency was up to 77.93% when the distance of electrodes was 10cm but negligible when the distance of electrodes was 50 cm. The addition of acid eg.HCl and citric acid to cathode compartment could increase the electric potential. The addition of EDTA to cathode compartment had negligible enhancement on the eletromigration efficience of cadmium.
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