Application of high resolution ICP-spectrometry to the determination of B,Be, Co,Mo and Sn in soils and similar matrices

The most sensitive emission lines for the elements B, Be, Co and Mo are strongly influenced by disturbing emission lines of Fe using normal optical resolution. The advantages of high resolution, applying the new ICP-spectrometer JY 38 Plus (Jobin-Yvon, France) with the 2400 lines/mm grating measuring in the 1st and 2nd order will be discussed. Beside the concentrations in soils, sediments and sludges, applying aqua regia and HF decomposition methods, the detection limits in these matrices will be given. The possibilities of ICP-spectrometry for the determination of the above-mentioned elements are shown at the examples of SRMs (standard reference materials). The materials used here were three soils and three sludges from the BCR (Community Bureau of Reference, European Communities) and one sediment from NBS (National Bureau of Standards, USA). For example, the most sensitive and normally used line for the determination of boron at 249.7733 nm cannot be used in case of this type of matrix due to normally high Fe-concentrations and due to a strong Fe-interference. Therefore, it is necessary to use the line at 249.6778 nm, where an interference-free measurement can be achieved in case of high optical resolution. The measured B-contents in these samples are in the range of 20 to 60 g/g, for Co in the 10 g/g region, for Be well below 1 g/g, for Sn between 3 and 400 g/g. Mo was only detectable in the sludge samples (limit of determination 0.5 g/g).Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria