Determination of uranium and thorium in zircon by energy dispersive X-ray fluorescence technique

Abstract

An energy dispersive X-ray fluorescence method has been developed for the determination of uranium and thorium in zircon, using synthetic powder standards containing uranium and thorium in the range 50 - 1000 ppm. After optimization of instrumental parameters, calibration is carried out using six synthetically prepared standards in pellet form. The experimental limits of detection for uranium and thorium analytes are found to be 200 and 100 ppm respectively. The accuracy of the method has been evaluated by measuring the concentration of uranium and thorium in two synthetic samples and is found to be about <span style="font-family:Symbol; mso-ascii-font-family:" times="" new="" roman";mso-hansi-font-family:"times="" roman";="" mso-char-type:symbol;mso-symbol-font-family:symbol"="" lang="EN-GB">± 5%. Three ore samples have been analyzed by the proposed method and by gamma spectrometry and/or neutron activation analytical techniques for uranium and thorium. The standardized method can be used for fast determination of uranium and thorium in zircon samples non-destructively with a precision of <span style="font-family:Symbol;mso-ascii-font-family:" times="" new="" roman";="" mso-hansi-font-family:"times="" roman";mso-char-type:symbol;mso-symbol-font-family:="" symbol"="" lang="EN-GB">± 5 - 20%.

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