Rare earth leach rates

In several respects, this ranking is not unexpected low charge, high mobility ions like Ca and Sr2+ should leach more easily than the rare earth and actinide elements. Although plutonium and cerium have similar properties as pure oxides, Plutonium was found to have a higher release rate than Cerium or Curium. Obviously, much more work is needed to understand these differences than was possible with this study. 

The agreement between these two tests indicated no significant change in leach rate with time on this short time scale, for the particular elements studied ( i.e.j barium, strontium, cerium, and rare earths). It was not possible to determine the cesium content in these granules because, for economy reasons, cesium was not included in the calcine production. The results of these measurements are given in Table III. Significant differences in the leach rates of the alkaline earths (barium, strontium) the RE (europium), and cerium are observable. 

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