A modified method to eliminate 210Bi interference in the analysis of 90Sr by extractive chromatography

Abstract

Background210Bi is one of the most important interferences in the analysis of 90Sr by extractive chromatography. It is verified by the leaching curve that bismuth and yttrium are completely adsorbed on the chromatographic column in the bis(2-ethylhexyl) phosphate (HDEHP) extraction chromatography, and this two components can not be completely separated, resulting in higher measurement results of 90Sr.PurposeThis study aims to provide a modified method to eliminate 210Bi interference in the analysis of 90Sr by bis(2-ethylhexyl) phosphate (HDEHP) extraction chromatography.MethodsBy collecting the eluent, measuring the content of strontium, yttrium, lead and bismuth in the eluent and drawing the leaching curve, the adsorption and elution behavior of strontium, yttrium, lead and bismuth in the P204 resin were investigated. The residual 210Bi after column separation was experimentally removed by Bi2S3 precipitation or by measuring the sample source repeatedly and correcting the result with formulas.ResultsThe experimental results show that the relative deviation between the modified 90Sr activity and the reference value is within 23% when the activity ratio of 210Bi to 90Sr is not bigger than 5. The results of 90Sr calculated by the modified method for environmental samples are in good agreement with the measured results after bismuth removal by Bi2S3 precipitation.ConclusionsThe interference of 210Bi in the analysis of 90Sr by extractive chromatography can be eliminated by measuring the sample source repeatedly and correcting the result with formulas.

Keywords

• strontium-90
• bismuth-210
• eliminate 210bi interference
• extraction chromatography
• correction method