Studies on Characteristics of High-energy Polarized Energy-dispersive X-ray Fluorescence Spectrometer and Determination of Major and Trace Elements in Geological Samples

Abstract

BACKGROUND The quantification of trace elements in geological samples depends largely on the analytical methods that require complex chemical pretreatment. High-energy polarized energy-dispersive X-ray fluorescence spectrometry (HE-P-EDXRF) has a considerable advantage for the determination of trace elements with large atomic numbers, due to its high-energy properties, which can effectively excite the Kα line of heavy elements. OBJECTIVES To establish a HE-P-EDXRF method for quantitative analysis of major and trace elements in geological samples. METHODS HE-P-EDXRF was used to establish an analysis method for major and trace elements in soil, rock and water system sediments. The selection of analysis lines, line overlap interference correction and matrix correction modes were discussed. Uncertainty was used to evaluate the method. RESULTS The Kα line was selected as the analysis line for trace elements with a larger atomic number due to less interference from the spectral line overlap, which is beneficial to obtaining the net peak intensity. Rare earth elements such as La, Ce and Nd can be accurately measured. Detection limits of the trace element Ba and rare earth elements such as La, Ce determined by EDXRF were greater than those determined by WDXRF, but lesser for light elements. For all the major and trace elements, the average of relative error of test training data was less than 15% except for Na2O, MgO, P and Sm. The average relative error of trace elements was between 2.40% and 16.3%. The accuracy of trace elements (except Cu and Yb) was significantly better than that of WDXRF. According to the evaluation method of the Europe Union, no significant difference existed between the trace elements results (except V and Th) and the recommended value of certified reference materials. CONCLUSIONS HE-P-EDXRF is a simple, fast and environmentally-friendly method that can simultaneously analyze multiple elements in geological samples. This method is suitable for quantification of the trace and rare earth elements in rock, soil and sediment, which overcomes the dependence of quantitative analysis of rare earth and trace elements in geological samples on the need for methods requiring complex chemical pretreatment.

Keywords

• high-energy polarized energy-dispersive x-ray fluorescence spectrometry
• geological samples
• pressed-powder pellets
• major and trace elements