Analysis of Non-Conducting Tantalite Minerals by Glow Discharge Optical Emission Spectrometry

Abstract

Capabilities of the radio frequency glow discharge optical emission spectroscopy (RF-GD-OES) for analysis of Ta2O5/Nb2O5 and tantalum and niobium in electrically non-conducting geological samples were investigated. The metal pentoxides (Ta2O5 and Nb2O5) and the tantalite mineral powders were mixed with a thermally conductive copper powder in ratios of up to 1:10 sample:copper and pressed into a disc sample for glow discharge sputtering. Studies were carried out to determine and optimize all the parameters affecting the analyses by the RF-GD-OES technique. This included the determination of the ability of the methodology to generate usable analytical curves for the target elements. Good calibration curves which were used for analyses of Ta and Nb in the tantalite minerals were obtained at optimized experimental conditions. Respective tantalum and niobium recoveries were in the order of 99.78–104.91% and 98.34–102.03% from the mineral analyses.