金属状コバルトによる60Coの捕捉

Abstract

It is well known that an exchangé reaction between metal and its ion in solution occurs at the surface of the metal.Using this exchange reaction technique, the removal of 60Co from an aqueous solution with cobalt metal has been studied. When 2 ml of 0.1 N or 1 N NaNO3 solution containing trace amounts of 60Co was shaked vigorously with 50 mg of cobalt metal (powder) for about 30 min, up to 95100% of 60Co was removed from the solution. The higher normality of HCl or HNO3 solution containing the tracer of 60Co was used, the lower rate of removal of 60Co from this solution was obtained. This experiment result may be due to the following reason, i.e., a part of cobalt metal was dissolved in acid solution and it resulted in the increase of the content of cobalt ion in this solution.It was found that up to 95100% of 60Co was rapidly removed from 0.5 N NaNO3 solution containing 10 μg of nickel per ml using this exchange reaction techniques with cobalt metal. In this experiment, however, about 40% of nickel was also deposited on cobalt metal and the separation of 60Co from nickel ion was not satisfactory.