Experimental Parameters for XRF Analysis of Soils

Harmful elements (Pb, Se, Cd, etc.) in the soil samples were measured by X-ray fluorescence (XRF) method. We investigated the influence of the thickness of soil layer, the grain size of soils, and the water content in soils on XRF intensity. Since high-energy XRF such as Cd K was detected in deep inside of soils, a thickness of 10 mm was recommended. The soil sample with a small grain size gave a relatively strong XRF intensity, especially for low-energy x-rays. Therefore, this grain-size effect should be taken into account for quantitative XRF analysis of the soil. It was also confirmed that water in soils decreased the XRF intensity, especially for low-energy x-rays. Preferably, after the soil sample was dried, the soils should be analyzed by XRF. Otherwise, XRF intensity has to be corrected depending on water content in the soil sample. INTRODUCTION X-ray fluorescence (XRF) analysis has been used in various fields, such as material research, environmental research, quality control of products, etc. This is because XRF has unique advantages of rapid non-destructive quantitative analysis in air. In this paper, XRF was applied for analysis of soils. There is a possibility that the soils are polluted with harmful elements, such as Pb, Cd, Hg, As due to the industrial emissions or others. 248 Copyright ©-International Centre for Diffraction Data 2010 ISSN 1097-0002