Spectrophotometric determination of uranium and iron using 2,4-dinitrosoresorcinol

A sensitive spectrophotometric method for the determination of uranium has been developed, based on measurement of the colour produced by the reaction of uranyl ions (UO22+) with 2,4-dinitrosoresorcinol (DNR). The method is best suited to the determination of 0.10-2.00 mg of uranium in 50 ml of solution. The effects of many other ions on the coloured complex formed were studied and some interferences were eliminated by carrying out the complex formation in the presence of ethyl acetate. The precision of the method was 0.52% (relative standard deviation) and the accuracy was found to be within this value. The reagent was used to determine uranium and iron simultaneously by measuring the mixed colours formed with DNR. (author)