Physical, Chemical and Structural Evolution of Zeolite-Containing Waste Forms Produced from Metakaolinite and Calcined Sodium Bearing Waste (HLW and/or LLW)

Technical Report · Mon Jun 27 00:00:00 EDT 2005

DOI:https://doi.org/10.2172/841087· OSTI ID:841087

Grutzeck, Michael W

Zeolites are extremely versatile. They can adsorb liquids and gases and serve as cation exchange media. They occur in nature as well cemented deposits. The ancient Romans used blocks of zeolitized tuff as a building material. Using zeolites for the management of radioactive waste is not a new idea, but a process by which the zeolites can be made to act as a cementing agent is. Zeolitic materials are relatively easy to synthesize from a wide range of both natural and man-made substances. The process under study is derived from a well known method in which metakaolin (an impure thermally dehydroxylated kaolinite heated to {approx}700 C containing traces of quartz and mica) is mixed with sodium hydroxide (NaOH) and reacted in slurry form (for a day or two) at mildly elevated temperatures. The zeolites form as finely divided powders containing micrometer ({micro}m) sized crystals. However, if the process is changed slightly and only just enough concentrated sodium hydroxide solution is added to the metakaolinite to make a thick crumbly paste and then the paste is compacted and cured under mild hydrothermal conditions (60-200 C), the mixture will form a hard ceramic-like material containing distinct crystalline tectosilicate minerals (zeolites and feldspathoids) imbedded in an X-ray amorphous hydrated sodium aluminosilicate matrix. Due to its lack of porosity and vitreous appearance we have chosen to call this composite a ''hydroceramic''.

• Research Organization: The Pennsylvania State University, University Park, PA 16802 (US)
• Sponsoring Organization: USDOE Office of Environmental Management (EM); USDOE Office of Science (SC) (US)
• DOE Contract Number: FG07-98ER45726
• OSTI ID: 841087
• Report Number(s): DOE/ER/45726-FINAL; TRN: US0502413
• Resource Relation: Other Information: PBD: 27 Jun 2005
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE WASTES, AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
36 MATERIALS SCIENCE
42 ENGINEERING
54 ENVIRONMENTAL SCIENCES
BUILDING MATERIALS
CATIONS
CEMENTING
GASES
KAOLINITE
MICA
MIXTURES
POROSITY
QUARTZ
RADIOACTIVE WASTES
SODIUM
SODIUM HYDROXIDES
TUFF
WASTE FORMS
WASTES
ZEOLITES
WASTE FORMS
HYDROCERAMIC
METAKAOLIN
GEOPOLYMER
ZEOLITES
SODIUM BEARING WASTE
SBW