EXTRACTION AND SPECTROPHOTOMETRIC DETERMINATION OF MICROGRAM QUANTITIES OF COBALT IN VARIOUS MATERIALS WITH ZINC DIETHYLDITHIOCARBAMATE

Cobalt is extracted with a benzene solution of zinc diethyldithiocarbamate. The excess of reagent and metals such as copper and nickel extracted with cobalt are removed by washing the organic phase with potassium cyanide solution. Other metals such as bismuth and lead are replaced by copper by shaking the organic phase with copper sulphate solution; the copper in the organic phase is removed by potassium cyanide solution. The absorbance of cobalt diethyldicarbamate in the organic phase is then measured at 325 nm. Down to 1 μg of cobalt in a few grams of uranium, thorium, aluminium, beryllium, and zircaloy can be readily determined. © 1969.