Compositions and Durabilities of Glasses for Immobilization of Plutonium and Uranium

Abstract

A document prepared for WASTE MANAGEMENT '95 CONFERENCE-PAPER FOR PUBLISHED PROCEEDINGS ONLY-ABSTRACT WAS APPROVED 10-13-94. at Tucson from 02/26/95 -03/02/95. DOE Contract No. DE-AC09-89SR18035This paper was prepared in connection with work done under the above contract number with the U. S. Department of Energy. By acceptance of this paper, the publisher and/or recipient acknowledges the U. S. Government's right to retain a nonexclusive, royalty-free license in and to any copyright covering this paper, along with the right to reproduce and to authorize others to reproduce all or part of the copyrighted paper. DISCL.RMERThis report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or-usefklness of any information, apparatus, product, or pro~ess disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, ABSTRACTInvestigations have been performed to determine the suitability of glass as a host for surplus fissile material removed from nuclear weapons. The U.S. Department of Energy -Office of Technology Development has sponsored research at the Savannah River Site to develop durable glass compositions that are compatible with high concentrations of plutonium and uranium. These investigations also being performed to provide baseline actinide glass durability and processing data.Two glass forming systems are being evaluated. One of the systems is a commercial borosilicate glass and the other an iron phosphate glass. Both glass systems have a very high degree of compatibility with actinide oxides and are considerably more durable than conventional high-level waste glasses. The iron phosphate glass has a melting temperature in the 1 100°C range and has the higher uranium and plutonium solubility. The borosilicate has a melting temperature in the 1425°C range and is the more durable (on the order of fused silica) glass.

Frit Development for High Level Waste Sludge Batch 5: Compositional Trends for Varying Aluminum Concentrations

“…In these discussions, the original values for Ce 2 O 3 , La 2 O 3 , PbO, SO 4 2-, and ZrO 2 are included for completeness (e.g., to allow a sum of oxides to be computed for the bias-corrected results). These bias-corrected values are the same as the original Ce 2 O 3 , La 2 O 3 , PbO, SO 4 2-, and ZrO 2 values.…”

“…The results include analysis of variance (ANOVA) investigations looking for statistically significant differences between the means of these groups for each of the oxides for each of the standards. The results from the statistical tests for the Bias-corrected measurements are indicated by a "bc" suffix, and such adjustments were performed for all of the oxides of this study except for Ce 2 O 3 , La 2 O 3 , PbO, SO 4 2-, and ZrO 2 . Both measured and measured-bc values are included in the discussion that follows.…”

“…Although minor differences were observed, they did not have a significant impact on the conclusions made in this study. Several of the study compositions showed retention of more than 0.5 wt% SO 4 2-in glass.…”

“…Previous studies have suggested neodymium and hafnium as possible surrogates for uranium in nuclear waste glasses. 3,4 For the first two glass compositions, neodymium was substituted for uranium and thorium on an oxide mass basis. For the next two glass compositions, hafnium was substituted for uranium and thorium on an oxide mass basis.…”

“…Figure 4-1 provides a plot of the measured versus targeted SO 4 2-values for each of the glasses over all the analytical plans (this plot is a compilation of three of the plots in Exhibit A5). …”