Spectrophotometric determination of micro-amounts of cobalt in uranium oxide, pure uranium and a uranyl salt with 2-nitroso-5-dimethylaminophenol

Abstract

Micro-amounts and trace amounts of cobalt in uranium oxide (U₃O₈), uranium and a uranyl salt were determined spectrophotometrically with 2-nitroso-5-dimethylaminophenol (nitroso-DMAP) reagent. According to the cobalt content (above 0·01 p.p.m.) of the sample, four methods for determining cobalt are recommended. By use of one method, cobalt in a sample containing more than 5 p.p.m. of cobalt was determined in aqueous solution, while by use of the other three methods, cobalt in samples containing more than 0·5, 0·1 and 0·01 p.p.m., was determined by a solvent-extraction-spectrophotometric method.