Solubility interpretation of leach tests

Conference · Fri Aug 01 04:00:00 EDT 1986

OSTI ID:6856640

Mendel, J E

The phenomenological behavior of commercial silicate glasses and nuclear borosilicate glasses in confined glass:aqueous solution systems is similar. For commercial silicate glasses the behavior has been described, ''If the neutral solution is unbuffered and confined in a bottle, it becomes alkaline and attack is accelerated, but eventually the accumulated products inhibit further action.'' Similar behavior is observed for nuclear waste borosilicate waste glasses in the MCC-1 Static Leach Test Method, the pulsed-flow test, and other leach tests in which the amount of solution in contact with the glass is restricted. In these tests the concentration of ions in the leachate increases initially (but not congruently, that is, the ratio of ion concentrations in the leachate is different than in the original glass), however, the concentration of each ion tends gradually towards its own steady-state concentration. The ''accumulated products'' that ''inhibit further action'', and result in the tendency toward steady-state leachate concentrations, are found in an altered layer on the surface of the leached glass and are generally considered to arise from solubility constraints. 21 refs., 2 figs., 2 tabs.

• Research Organization: Pacific Northwest Lab., Richland, WA (USA)
• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6856640
• Report Number(s): PNL-SA-13797; CONF-860905-27; ON: DE87004497
• Country of Publication: United States
• Language: English

Related Subjects

052002 -- Nuclear Fuels-- Waste Disposal & Storage
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
360604* -- Materials-- Corrosion
Erosion
& Degradation
BOROSILICATE GLASS
DISSOLUTION
GLASS
LEACHING
QUANTITY RATIO
SEPARATION PROCESSES
SOLUBILITY