Mathematical elimination of spectral interferences in the direct determination of rare-earth elements in natural waters by inductively coupled plasma quadrupole mass spectrometry

Abstract

The paper presents original mathematical models for the elimination of oxide and hydroxide spectral interferences with analytical masses of rare-earth elements for a quadrupole instrument in the mode oriented on the introduction of low-mineralized samples without using collision gas helium. A single model for the elimination of spectral interferences with elements from La to Dy in the composition and also three models for the elimination of spectral interferences with Ba in the composition are presented. The efficiencies of the last three proposed models are compared between themselves and with the previously used approach described in the literature. The relative intensities of oxide and hydroxide ions of elements from Ba to Dy are shown. Concentrations of Ba and rare-earth elements were estimated in six river water samples from the Primorskii Krai (Russia). They can be used for the correct interpretation of the hydrogeochemical behavior of elements (especially of Eu, Gd, and Tb). A method for calculating integration time is presented.