PREPARATION OF SPIKED CS-137/CS-134 ZEOLITE MOLECULAR-SIEVE 4A FOR USE AS ENVIRONMENT CALIBRATION STANDARDS

Inorganic caution exchangers like granular molecular sieve 4A (80% zeolite 4A. 20% bentonite) are suitable matrices for the preparation of low density (rho congruent-to 0.75 g . ml-1) radioactive calibration standards required in environment nuclear metrology. The present paper describes, in detail. the study of a chromatographic method usable for the preparation of Cs-137/Cs-134 spiked molecular sieves 4A. Spiked samples produced with this method are characterized in terms of nuclear homogeneity and activity concentration. In the near future, the traceability of these matrices to primary and secondary standards will be undertaken by an intercomparison of measurements between European primary laboratories.