Fused Pellet-Determination of 16 Elements in Copper Ores by X-ray Fluorescence Spectrometry

Accuracy and precision of the analytical results for major and minor components in copper ores by the X-ray Fluorescence Spectrometry (XRF) fusion method can be seriously affected by the type of copper ore being analysed and the complex components it contains. The existing XRF analysis method is limited by the following factors: only having a small number of reference materials and ore types, single and wide scope of analysis not matching the actual samples, and low quality of pellet. In this study, we choose 24 ores of reference materials including copper, gold, silver, lead, zinc, molybdenum, copper and nickel which has a good range of copper content with common Cu levels. Lithium tetraborate-lithium metaborate-lithium fluoride was used as flux, the ratio of flux and sample being 30:1. Using LiBr as the release agent, the high quality melt sheet was prepared by adding later mixed flux which completely covered the release agent, but not by adding release agent after the pre-oxidation or during molten, as is the most common method used. The quantitative analytical method for determination of 16 elements including Cu, Zn, Pb, SiO₂, Al₂O₃, TFe₂O₃, TiO₂, MnO, CaO, K₂O, MgO, Mo, Bi, Sb, Co and Ni in copper ore by X-ray fluorescence spectrometry with fused pellet was established. The method was verified by the analysis of the copper ore certified reference materials of GBW 07164 and GBW 07169, and the relative standard deviations (RSD) were from 0.1% to 5.4%. Analysis results of certified reference materials (GBW 07163, GBW 07170) which did not participate in regression were basically in good agreement with certified values. The results of Cu, Zn, Pb, Mo, Bi, Sb, Co and Ni for practical samples by the proposed method were consistent with those obtained by Inductively Coupled Plasma Spectrometry and other analysis methods. The method expanded the adaptability of ore matrix and improved value in the practical application.