Insolubilization of cadmium in paddy field using atomized iron powder and extracting reagent.

The insolubilization of cadmium in the soil of a naturally cadmium-contaminated paddy field was studied using an atomized iron powder and an extracting reagent. Cadmium in the soil was extracted into the water phase by calcium chloride. The extracted cadmium was deposited on the iron powder. The deposition of cadmium was significantly influenced by calcium chloride, since the surface area of the iron powder increased with the increasing calcium chloride concentration. We discuss the potential of the technique and the insolubilization mechanism.