Evaluation of Solution Composition Aluminoborosilicate Waste Glass Dissolution at 40°C

Conference · Wed Feb 28 23:00:00 EST 2007

OSTI ID:910004

Richards, Emily L; Davis, Aaron M; Pierce, Eric M

Single-pass flow-through experiments were conducted with aluminoborosilicate waste glasses to evaluate how changes in solution composition affect the dissolution rate (r) at 40°C and pH(23°C) = 9.0. The three prototypic low-activity waste (LAW) glasses; LAWE-1A, -95A, and -290A, used in these experiments span a wide range covering the expected processing composition of candidate immobilized low-activity waste (ILAW) glasses. Results suggest incongruent release of Al, B, Na, and Si at low flow-rate (q) to sample surface area (S) [log10 (q/S) < -8.9 (m/s)] whereas congruent release was observed at high q/S [log10 (q/S) > -7.9 (m/s)]. Forward dissolution rates, based on boron release, are the same irrespective of glass composition, evident by the dissolution rates being within the experimental error of one another [r1A = 0.0301 ±0.0153 g/(m2 d), r95A = 0.0248 ±0.0125 g/(m2 d), and r290A = 0.0389 ±0.0197 g/(m2 d)]. Finally these results support the use of a chemical affinity based rate law to describe glass dissolution as a function of solution composition.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 910004
• Report Number(s): PNNL-SA-52923; 14592; 830403000
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
ALUMINIUM OXIDES
BOROSILICATE GLASS
CHEMICAL COMPOSITION
CHEMICAL REACTION KINETICS
DISSOLUTION
Environmental Molecular Sciences Laboratory
FLOW RATE
LAW
LOW-LEVEL RADIOACTIVE WASTES
SURFACE AREA
WASTE FORMS
dissolution kinetics
low-activity waste glass