Determination of Selenium, Major and Minor Elements in Selenium-rich Soil Samples by X-ray Fluorescence Spectrometry with Powder Pellet Preparation

Abstract

BACKGROUND At present, the content of Se in soil is mainly determined by atomic fluorescence spectrometry, which has disadvantages such as large usage of acid and relatively complex pretreatment. Determination of high content of Se requires high dilution, which expands the analysis error. OBJECTIVES To establish a method for the determination of Se and other elements in Se-rich soil samples by wavelength dispersive and energy dispersive X-ray fluorescence (WD-ED XRF). METHODS WD-ED XRF was used to determine 17 major and minor elements such as Se in Hubei selenium-rich soil samples with powder pellet. While 10 elements were analyzed by WD-XRF, As, Cu, Rb, Sr, Zr, Ba, Ni were analyzed by ED-XRF, which significantly reduced the measurement time. RESULTS By mixing different certified reference materials in proportion to configure mixed certified reference materials, the problem of insufficient content of the existing Se reference materials in the range of 5-72μg/g was solved. For the determination of high content Se, the relative standard deviation was less than 10%, and the RSD of high content Se sample was less than 0.70%, through the precision and accuracy assessment. CONCLUSIONS The proposed method satisfies the quantitative analysis of soil samples with Se content greater than 3.00μg/g, and provides the quantitative or approximate quantitative analysis results of 16 major and minor elements.

Keywords

• selenium-rich soil samples
• selenium
• major and minor elements
• powder pellet
• x-ray fluorescence spectrometry
• mixed certified reference materials