Application Brief

Elemental Analysis of Nickel Laterite Ore Prepared as Pressed Pellets With SPECTROCUBE

The main target of the elemental analysis of nickel laterite ore is the accurate determination of the content of nickel, iron, and cobalt. In addition, the analysis of other elements like Mg, Al, Si, Ca, Cr, Mn, and others is also of interest. As the analysis should be done on the mine site, the sample prep should be easy. Therefore, the sample preparation as pressed pellet is typically used.

When standard energy-dispersive X-ray fluorescence spectrometry (ED-XRF) is used as technique for this type of analyses, the accurate determination of the cobalt content is limited as an interference from Fe K_β on Co K_α has to be considered. In addition the Co K_β is overlapped by the Ni K_α line. Another effect can be relevant as well: When applying standard reference spectra for deconvolution, the ratio between the K_α and K_β lines will depend on the concentrations of other elements in the sample, as for example Fe K_β will be absorbed by Mn whereas Fe K_α will be not. Traditional XRF approaches using line overlap corrections are applied but this does not lead to best possible accuracy. This approach cannot be considered as universal as it is limited to the range of calibration samples. When looking at various required empirical corrections for these effects, the number of calibration samples increases as 2n+1 reference samples should be used for the determination of n parameters.

Learn more in this informative application report.