Determination of barium in calcium carbonate rocks by carbon furnace atomic-emission spectrometry

Abstract

A simple and rapid method is described for the determination of barium at 0.5–30 µg g^–1 concentrations in calcium carbonate and limestone rocks. The sample is dissolved in nitric acid, caesium is added as an ionisation suppressor and the resulting solution is analysed by using carbon furnace atomic-emission spectrometry with automatic background correction using wavelength modulation. Spectral interference from CaOH band structure is low in the carbon furnace compared with flame atomisation and is removed by background correction. Other matrix interferences are negligible. The reproducibility is 5.9% at the 2.4 µg g^–1 level and the detection limit is 0.036 µg g^–1 of barium in rock samples.