Tracer Studies on Sr Resin and Determination of 90Sr in Environmental Samples

Rožle Jakopič and Ljudmila Benedik
Department of Environmental Sciences, Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia, E-mail: rozle.jakopic@ijs.si

Abstract
In this work various tracer experiments were performed to investigate the elution behaviour of some radionuclides on Sr resin, matrix effects of calcium and potassium and the resin capacity for strontium. None of the studied radionuclides interfered with the separation of strontium since all were washed out with 3M HNO3 before the elution step with water, except barium. Barium and strontium were separated using 8M HNO3. The maximum resin capacity for strontium was 8.1 mg of Sr/g of Sr resin. Up to 2 g of calcium and 200 mg of potassium can be loaded on the Sr column (3 g Sr.spec) without decrease in strontium recovery. The separation procedure using Sr resin was tested on soil samples spiked with 90Sr standard solutions and on reference materials. All results obtained by this method gave good agreement. Counting sources were prepared by weighing SrC2O4 on a planchet. The 90Sr content was measured with a proportional gas flow beta counter after secular equilibrium between 90Sr and 90Y was reached. The chemical recovery was determined gravimetrically and was always higher than 80%.  

Key words: Sr resin, extraction chromatography, 90Sr, beta counting