Analysis of River Sand for Thorium, Yttrium and Zirconium by X-Ray Fluorescence and Optical Emission Spectrographic Methods

摘要

X-ray fluorescence (XRF) and optical emission spectrographic (OES) methods for the determination of Th, Y and Zr in river sand samples have been described. For XRF analysis the sample is mixed with boric acid (1:1) and made into a pellet. Using tungsten target tube for irradiation, LiF (200) crystal for dispersion and scintillation counter for detection, the analysis is done in the range 0.005 - 1%. For OES analysis the sample is mixed with pure graphite (1:1), loaded in an under-cut electrode, excited in a DC arc and the spectrum is recorded on a grating spectrograph. Using the intensity ratio of Th 2837.3 A, Y 3327.9 A and Zr 3392.0 A with Pd 3242.7 A, the analysis is done in the range 0.001 - 0.02% for Y and Zr and 0.05 - 1% for Th. The precision of the analysis is calculated and the accuracy has been assessed by analysing the samples by the two methods. (Atomindex citation 12:574904)