Evaluation in the Application of Multi-instrument Synergy X-ray Fluorescence Spectrometry in a Regional Geochemical Survey

Abstract

Multi-element analysis of a regional geochemical survey sample usually involves X-ray Fluorescence Spectrometry (XRF), Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES), Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), Atomic Fluorescence Spectrometry (AFS) and other instruments. Because there are more than 20 elements determined by XRF, the detection speed of XRF is not synchronous with other instruments, which influences the overall progress of the project. The matching scheme is optimized, and the analysis method of XRF for part of the elements is adjusted in this study. The data of Na2O, MgO and V involved in matrix correction and spectral overlap correction are measured by ICP-OES. The data of Cu, Pb, Zn, Mn, and Th were measured by ICP-MS. As and Bi data were measured by AFS. The optimized XRF method reduces the number of elements to 16, namely SiO2, Al2O3, CaO, Fe2O3, K2O, Ti, P, Sr, Ba, Zr, Nb, Y, Rb, Br, Ga and Cl. Through the designed XRF data reduction program, the data sharing of different analysis methods is realized, and the influence of XRF data caused by matrix effects and spectral line overlap is corrected using the data from XRF, ICP-OES, ICP-MS and AFS. The precision of this method (RSD, n=12) is 0.55%-8.22%, and the accuracies (△logC) are 0-.0.031. The method is validated by determination of national standard reference materials and actual samples. The results meet the quality requirements for a regional geochemical survey. This scheme reduces the number of elements directly measured by XRF, and improves the analysis efficiency of various collaborative instruments.

Keywords

• regional geochemical survey analysis
• multi-instruments coordination
• x-ray fluorescence spectrometry
• matrix effect