XRFS Determination of Major and Minor Components in Zinc Concentrates with Fusion Sample Preparation

Major and minor componental elements(i.e., Zn, S, Fe, Si, Pb, Cu, As, Ag, Cd, Sn and Sb) in zinc concentrates were determined by XRFS. The sample (0.6 g) was mixed with 6.3 g of Li2B4O7 and 3.2 g of LiNO3 in a Pt-Au crucible and heated firstly at 500 ℃ and then at 700 ℃ for 10 min to pre-oxidize S2- in the sample to SO42-. A flux mixture of Li2B4O7 and LiBO2 was formed during the course of preoxidation and acted as flux to fuse the sample at 1 030 ℃ for 10 min. The molten melt was transferred into the sample mould, and after cooling, the melt was unloaded from the mould, and used for XRFS analysis. To eliminate the interferences arised from alteration of composition and increase of mass during preoxidation and fusion of sample, the method of variable α influential coefficient based on sherman equation was used in the correction. The ranges of calibration curves were found to cover from 27% to 62% for Zn and from 10% to 35% for S with values of standard deviation less than 0.2% for both Zn and S. In the analysis of 2 CRM′s (GBW 07168 and SRM 113b) by this method, results obtained were in consistency with the certified values.