Crystalline-phase formation in hot isostatic pressing of nuclear waste ceramics with high zirconia content

Journal Article · Fri Mar 01 04:00:00 EST 1985 · J. Am. Ceram. Soc.; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1985.tb09657.x· OSTI ID:5188348

Harker, A B; Flintoff, J F

Ceramic forms with a significant glass phase have been prepared from Zr-rich simulated Idaho Chemical Processing Plant high-level nuclear waste by hot isostatic pressing of redox-controlled waste and chemical additive calcines. Crystalline-phase formation in the ceramics is a function of the waste loading, additives, and consolidation temperature. Actinide host phases are controlled by silica-zirconia crystal chemistry; the composition of the amorphous phase dominates the leaching behavior. Two phase assemblages -- one consisting of CaF/sub 2/, ZrO/sub 2/, ZrSiO/sub 4/, and glass, the second of CaF/sub 2/, ZrO/sub 2/, YNaSiO/sub 4/, ZrSiO/sub 4/, and glass -- showed leach resistance superior to melter-processed borosilicate glass forms for uranium and, at waste loadings >80 wt%, offer a factor of up to 3.2 times greater volume reduction. The presence of the designed glass phase in the waste forms makes them more flexible to variations in waste composition and lowers the required hot isostatic pressing temperature for consolidation as compared with polycrystalline waste ceramics, while maintaining the actinide leach resistance of the crystalline phases.

• Research Organization: Rockwell International Science Center, Thousand Oaks, California
• OSTI ID: 5188348
• Journal Information: J. Am. Ceram. Soc.; (United States), Journal Name: J. Am. Ceram. Soc.; (United States) Vol. 68:3; ISSN JACTA
• Country of Publication: United States
• Language: English

Related Subjects

052001* -- Nuclear Fuels-- Waste Processing
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360202 -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
ACTINIDES
ADDITIVES
ALKALI METAL COMPOUNDS
ALKALINE EARTH METAL COMPOUNDS
AMORPHOUS STATE
BOROSILICATE GLASS
CALCIUM COMPOUNDS
CALCIUM FLUORIDES
CALCIUM HALIDES
CERAMICS
CHALCOGENIDES
CRYSTAL GROWTH
CRYSTAL-PHASE TRANSFORMATIONS
DISSOLUTION
ELEMENTS
FABRICATION
FLUORIDES
FLUORINE COMPOUNDS
GLASS
HALIDES
HALOGEN COMPOUNDS
HIGH-LEVEL RADIOACTIVE WASTES
HOT PRESSING
LEACHING
MANAGEMENT
MATERIALS
MATERIALS WORKING
METALS
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PRESSING
PROCESSING
RADIOACTIVE MATERIALS
RADIOACTIVE WASTE PROCESSING
RADIOACTIVE WASTES
SEPARATION PROCESSES
SILICA
SILICON COMPOUNDS
SILICON OXIDES
SODIUM COMPOUNDS
SODIUM OXIDES
TEMPERATURE DEPENDENCE
TRANSITION ELEMENT COMPOUNDS
VITRIFICATION
WASTE FORMS
WASTE MANAGEMENT
WASTE PROCESSING
WASTES
YTTRIUM COMPOUNDS
YTTRIUM OXIDES
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES