Ion Exchange Column Tests Supporting Technetium Removal Resin Maturation

Technical Report · Fri Dec 20 04:00:00 EST 2013

DOI:https://doi.org/10.2172/1332667· OSTI ID:1332667

Nash, C. ^[1]; McCabe, D. ^[1]; Hamm, L. ^[1]; Smith, F. ^[1]; Morse, M. ^[1]

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1. Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

The primary treatment of the tank waste at the DOE Hanford site will be done in the Waste Treatment and Immobilization Plant, currently under construction. The baseline plan for this facility is to treat the waste, splitting it into High Level Waste (HLW) and Low Activity Waste (LAW). Both waste streams are then separately vitrified as glass and sealed in canisters. The LAW glass will be disposed on site. There are currently no plans to treat the waste to remove technetium, so its disposition path is the LAW glass. Due to the soluble properties of pertechnetate and long half-life of ⁹⁹Tc, effective management of ⁹⁹Tc is important. Options are being explored to immobilize the supplemental LAW portion of the tank waste, as well as to examine the volatility of ⁹⁹Tc during the vitrification process. Removal of ⁹⁹Tc, followed by off-site disposal has potential to reduce treatment and disposal costs. A conceptual flow sheets for supplemental LAW treatment and disposal that could benefit from technetium removal will specifically examine removing ⁹⁹Tc from the LAW feed stream to supplemental immobilization. SuperLig® 639 is an elutable ion exchange resin. In the tank waste, ⁹⁹Tc is predominantly found in the tank supernate as pertechnetate (TcO₄^-). Perrhenate (ReO₄^-) has been shown to be a good non-radioactive surrogate for pertechnetate in laboratory testing for this ion exchange resin. This report contains results of experimental ion exchange distribution coefficient and column resin maturation kinetics testing using the resin SuperLig® 639a to selectively remove perrhenate from simulated LAW. This revision includes results from testing to determine effective resin operating temperature range. Loading tests were performed at 45°C, and the computer modeling was updated to include the temperature effects. Equilibrium contact testing indicated that this batch of SuperLig® 639 resin has good performance, with an average perrhenate distribution coefficient of 291 mL/g at a 100:1 phase ratio. This slightly exceeds the computer-modeled equilibrium distribution. The modeling agreed well with the experimental data for perrhenate removal with minor adjustments. Predicted breakthrough performance was on average within about 20% of measured values.

• Research Organization: Savannah River Site (SRS), Aiken, SC (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC09-08SR22470
• OSTI ID: 1332667
• Report Number(s): SRNL--STI-2013-00573
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
COMPUTERIZED SIMULATION
DISTRIBUTION
EQUILIBRIUM
EXPERIMENTAL DATA
FLOWSHEETS
GLASS
HANFORD RESERVATION
ION EXCHANGE MATERIALS
KINETICS
LOADING
LOW-LEVEL RADIOACTIVE WASTES
MATURATION
PERFORMANCE
PERRHENATES
PERTECHNETATES
RADIOACTIVE WASTE PROCESSING
REMOVAL
RESINS
TANKS
TECHNETIUM
TECHNETIUM 99
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE
TEMPERATURE RANGE 0273-0400 K
TESTING
VITRIFICATION
VOLATILITY