Tritium release from irradiated lithium aluminate, can it be improved

Lithium aluminate is an attractive material (in terms of its chemical, mechanical and irradiation properties) for breeding tritium in fusion reactors; however, its tritium release characteristics are not as good as those of other candidate materials. To investigate whether tritium release from lithium aluminate can be improved, we have studied the tritium release from irradiated samples of pure lithium aluminate, lithium aluminate doped with Mg, and lithium aluminate with a surface deposit of platinum. The release was studied by the temperature programmed desorption (TPD) method. Both the platinum coating and magnesium doping were found to improve the tritium release characteristics, as determined by TPD. Tritium release shifted to states with lower activation energies for the altered materials

Tritium release from irradiated lithium aluminate, can it be improved?

Lithium aluminate is an attractive material (in terms of its chemical, mechanical and irradiation properties) for breeding tritium in fusion reactors; however, its tritium release characteristics are not as good as those of other candidate materials. To investigate whether tritium release from lithium aluminate can be improved, we have studied the tritium release from irradiated samples of pure lithium aluminate, lithium aluminate doped with Mg, and lithium aluminate with a surface deposit of platinum. The release was studied by the temperature programmed desorption (TPD) method. Both the platinum coating and magnesium doping were found to improve the tritium release characteristics, as determined by TPD. Tritium release shifted to states with lower activation energies for the altered materials

Relative availability of selected trace elements from coal fly ash and Lake Michigan sediment

The concentration of greater than 1 ..mu..m coal fly ash particles in Lake Michigan surface waters was found to be 10/sup 5/ to 10/sup 6/ per liter. With an expected residence time of one year, this concentration implies a flux to the sediment of 10/sup 6/ to 10/sup 7/ particles/cm/sup 2//yr, or about 10/sup -6/ to 10/sup -5/ g/cm/sup 2//yr. The release of trace elements from fly ash and sediment has been studied using Chelex-100 resin to simulate leaching at high dilutions in natural media. Mn, Pb and Zn, but not Fe, are released more readily from Lake Michigan sediment than from fly ash

Argonne National Laboratory Reports

A strategy for the experimental validation of waste package performance assessment has been developed as part of a program supported by the Repository Technology Program. The strategy was developed by reviewing the results of laboratory analog experiments, in-situ tests, repository simulation tests, and material interaction tests. As a result of the review, a listing of dependent and independent variables that influence the ingress of water into the near-field environment, the reaction between water and the waste form, and the transport of radionuclides from the near-field environment was developed. The variables necessary to incorporate into an experimental validation strategy were chosen by identifying those which had the greatest effect of each of the three major events, i.e., groundwater ingress, waste package reactions, and radionuclide transport. The methodology to perform validation experiments was examined by utilizing an existing laboratory analog approach developed for unsaturated testing of glass waste forms

Strategy for Experimental Validation of Waste Package Performance Assessment

A strategy for the experimental validation of waste package performance assessment has been developed as part of a program supported by the Repository Technology Program. The strategy was developed by reviewing the results of laboratory analog experiments, in-situ tests, repository simulation tests, and material interaction tests. As a result of the review, a listing of dependent and independent variables that influence the ingress of water into the near-field environment, the reaction between water and the waste form, and the transport of radionuclides from the near-field environment was developed. The variables necessary to incorporate into an experimental validation strategy were chosen by identifying those which had the greatest effect of each of the three major events, i.e., groundwater ingress, waste package reactions, and radionuclide transport. The methodology to perform validation experiments was examined by utilizing an existing laboratory analog approach developed for unsaturated testing of glass waste forms. 185 refs., 9 figs., 2 tabs