DETERMINATION OF TRANSITION-METALS IN NUCLEAR-REACTOR WATERS - A REVIEW

There is a need to study the transition metal concentrations in the pr imary coolant of nuclear reactors. The very low concentrations of espe cially cobalt, down to 0.5 ng/l in some pressurised water reactors, bu t also iron, manganese and nickel, and the high boric acid concentrati ons in pressurised water reactors, render the sampling and analysis pr oblematic. There is considerable doubt: about the possibility of getti ng representative samples. In most cases the water samples have to be preconcentrated, usually by chelating chromatography or cation filters . A number of different analytical techniques have been used. The by f ar most published results have been determined with on-line ion chroma tography. Other methods used are atomic absorption spectrophotometry, usually the graphite furnace variant, inductively coupled plasma atomi c emission- and mass spectrometry, neutron activation analysis, X-ray fluorescence and voltammetry. The methods are discussed with special e mphasise on the detection limits.