C. C. Herman, D. R. Best, I. A. Reamer, and R. J. Workman
Westinghouse Savannah River Company
Aiken, SC 29808

This 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 usefulness of any information, apparatus, product or process 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, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

This report has been reproduced directly from the best available copy.

Available for sale to the public, in paper, from:  U.S. Department of Commerce, National Technical Information Service, 5285 Port Royal Road, Springfield, VA 22161,  phone: (800) 553-6847,  fax: (703) 605-6900,  email:  orders@ntis.fedworld.gov   online ordering:  http://www.ntis.gov/support/index.html

Available electronically at  http://www.osti.gov/bridge/

Available for a processing fee to U.S. Department of Energy and its contractors, in paper, from: U.S. Department of Energy, Office of Scientific and Technical Information, P.O. Box 62, Oak Ridge, TN 37831-0062,  phone: (865 ) 576-8401,  fax: (865) 576-5728,  email:  reports@adonis.osti.gov

Abstract

The Savannah River Technology Center (SRTC) has participated in a round robin testing program, which was conducted under the auspices of the Department of Energy’s Tanks Focus Area (TFA) for Immobilization. The round robin, lead by Argonne National Laboratory (ANL), focused on leach testing data of the Ceramic Waste Form (CWF) using the Product Consistency Test (PCT) (ASTM C 1285) and the ANL developed Rapid Water Soluble (RWS) procedure. The CWF is a heterogeneous material comprised of about 70% sodalite, 25% borosilicate glass binder, 3% halite, and 2% mixed rare earth and actinide oxides, by mass.

ANL provided SRTC with one vial of CWF material. The vial contained approximately 5 grams of pre-ground ceramic, which was sufficient to perform the PCT and the RWS.

The PCT was performed in triplicate and the RWS solutions were analyzed in triplicate for the CWF sample. The SRTC-ML provided support for the solution analysis via Inductively Coupled Plasma – Atomic Emission Spectroscopy and Ion Chromatography. The results of the PCT leachate and RWS decant analyses were corrected for the dilution/acidification as necessary. The corrected values are reported in mg/L for both sets of data.

The Savannah River Technology Center (SRTC) has participated in a round robin testing program which was conducted under the auspices of the Department of Energy’s (DOE) Tanks Focus Area (TFA) for Immobilization. The round robin is being lead by Argonne National Laboratory (ANL) and is focused on data regarding the Product Consistency Test (PCT) (ASTM C 1285) and the ANL developed Rapid Water Soluble (RWS) procedure on the Ceramic Waste Form (CWF). The CWF is a heterogeneous material that is comprised of approximately 70% sodalite, 25% borosilicate glass binder, 3% halite, and 2% mixed rare earth and actinide oxides, by mass. The sample for this study did not contain radionuclides. The CWF was developed to immobilize radioactive waste salt from treatment of spent sodium-bonded nuclear fuel.

The sample of CWF supplied by ANL was washed at ANL six times with 100% ethanol to remove the fines. Along with the sample, ANL provided guidance and data sheets for performing the RWS and the PCT. This report describes the experimental procedures, analytical techniques utilized, and the results obtained for the CWF sample using the RWS and the PCT protocols.

SRTC received one small vial (labeled RWS-SRTC-1) containing approximately 5 grams of the CWF material from ANL. Information accompanying the sample indicated that the vial contained –100, +200 mesh size fractions which had been washed with ethanol to remove the fines.

The RWS was performed by placing 5.018 g of the CWF sample in a beaker. Demineralized water was then added at an amount equivalent to 10 times the CWF sample mass (i.e., 50.181 g). The sample was ultrasonicated for 2 minutes and then allowed to settle for 60 seconds. The decanted solution was then filtered with a 0.45 m m filter and the solution was prepared for analyses. Approximately 5 ml of the solution, which was identified as the nonacidified RWS fraction, was submitted to the SRTC-ML for Ion Chromatography (IC) analyses for Cl. An additional ~5 ml of sample was acidified using 3 drops of high purity concentrated nitric acid and was submitted to the SRTC-ML for Inductively Coupled Plasma – Atomic Emission Spectroscopy (ICP-AES) analyses for Na. The CWF sample was then dried at 90° C overnight and stored in a sealed container until ready for use in the PCT.

The SRTC-ML performed Cl analyses for the nonacidified fraction from the RWS using procedure 1.11, "Anion Analysis Using the Dionex DX-500 Ion Chromatograph", of the L28 manual. The solution had to be diluted 10 fold so it was within the linear calibration range of 1 to 10 mg/L, and the resulting dilution was analyzed in triplicatethree times. Analysis for Na in the acidified fraction from the RWS was performed using procedure 1.16, "Inductively Coupled Plasma-Atomic Emission Spectrometer Varian Vista AX", of the L28 manual. The solution was diluted 100 fold and was analyzed in triplicate.

The PCT was performed in triplicate on the CWF sample that had been subjected to the RWS. The PCT-A procedure was used (ASTM C1285) starting with step 21.1 since the sample was already ground, sieved, and washed. The only deviations from standard operating procedure were that the vessels were only cooled for 5 minutes before weighing and that the pH was measured within 1 hour of removal from the oven. Both of these are usually performed after the vessels have cooled completely; however, the ANL guidance memo indicated that these deviations should be performed to provide consistency between the different labs performing the test. Per the PCT procedure, blanks from the PCT test and a multi-element solution standard were submitted for control purposes. Although not required by the guidelines from ANL, an ARM and EA glass were also tested with the CWF to assist in validation of the PCT test conditions. Approximately 5 ml of the unfiltered solutions from the blank and CWF samples were removed and submitted for IC analyses for Cl. For the filtered solution from the blank and CWF samples, 3 drops of high purity concentrated nitric acid were added to prepare the sample for ICP-AES analyses. The ARM and EA samples were diluted using the normal PCT protocol (i.e., 3 ml of leachate sample diluted with 2 ml of 0.4 M HNO₃ nitric acid).

The SRTC-ML performed Cl analyses on the unfiltered solution using procedure 1.11, "Anion Analysis Using the Dionex DX-500 Ion Chromatograph", of the L28 manual. The solution had to be diluted 3 fold so it was within the linear calibration range of 1 to 10 mg/L. The filtered solution was analyzed for Al, B, Li, Na, and Si using procedure 1.16, "Inductively Coupled Plasma-Atomic Emission Spectrometer Varian Vista AX", of the L28 manual. The solution was diluted 10 fold.

The results from the triplicate analyses of the nonacidified and the acidified RWS fractions are given in Table I. The Cl data is as reported by the SRTC-Mlsince acidification was not performed, while the Na data is corrected for the acid dilution. The average and standard deviation of the data is also reported.

Quality control standards were used with the analyses of the RWS nonacidified and acidified fractions and indicated that the matrix standards were within 10% of their expected values. Therefore, the data were considered acceptable. The measured values for the quality control standards are given in Appendix A.

Table II summarizes the initial weight (vessel, sample, and water), final weight, and % loss. The % loss was calculated based on water loss alone (i.e., vessel weight was not considered). All tests are considered valid based on the loss percentage (i.e., < 5%).

The results of the leachate analyses were corrected for the acidification of the leachate performed prior to submittal to the SRTC-ML for analysis and for the dilution necessary to perform the analysis. The corrected values are reported in mg/L in Table III. Cl was not measured for the ARM or EA samples.

Jantzen, et al. [Jantzen 1995], control charted the leachate concentrations for B, Si, Na, and Li obtained by the PCT procedure on ARM-1 glasses over a six year span. From these data, a mean, a lower control limit (LCL) and an upper control limit (UCL) were identified for each of the elements and for the pH of the leachate. The leachate concentrations for B, Si, Na, and Li and the pH are compared to the mean, LCL, and UCL in Table IV to validate the PCT test conditions.

Characterization of the DWPF Environmental Assessment (EA) glass was also performed by Jantzen, et. al. [Jantzen 1992], including PCT analyses. Table V presents the mean and standard deviation of the PCT durability measurements for the characterization. The results from CWF round robin PCT are compared to the characterization results. Measured values were within the accepted range for the EA glass.

Elemental values (mg/L) for the solution standard are compared to measured values reported by the SRTC-ML in Table VI. The solution standard was run with the PCT solutions during the ICP-AES analysis for control purposes. All measured values were within 5% of the solution standard acceptable rangesvalues.

Check standards were used with the analyses of the PCT leachates and indicated that the matrix standards were within 10% of their expected values. Therefore, the data were considered acceptable.

Standardized Test Methods for determining Chemical Durability of Nuclear Waste Glasses: The Product consistency Test (PCT), Standard C 1285-97, annual Book of ASTM Standards, Vol. 12.01, American Society for Testing and Materials, West Conshohocken, PA.

C.M. Jantzen, M.A. Pickett, K.G. Brown, T.B. Edwards, and D.C. Beam, Process/Product Models for the Defense Waste Processing Facility (DWPF): Part 1. Predicting the Glass Durability from Composition Using a Thermodynamic Energy Hydration MOdel (THERMO) (U), Westinghouse Savannah River Company, WSRC-TR-93-672, Rev. 1 (1995).

C.M. Jantzen, N.E. Bibler, D.C. Beam, C.L. Crawford, and M.A. Pickett, Characterization of the Defense Waste Processing Facility (DWPF) Environmental Assessment (EA) Glass Reference Material (U), Westinghouse Savannah River Company, WSRC-TR-92-346, Rev. 1 (1992).