Michele A Lewis

US Patent:

H12270, Sep 7, 1993

Filed:

Aug 14, 1991

Appl. No.:

7/744753

Inventors:

Michele A. Lewis - Naperville IL
Terry R. Johnson - Wheaton IL

Assignee:

The United States of America as represented by the Department of Energy - Washington DC

International Classification:

C21F 916

US Classification:

252628

Abstract:

The invention is a method for the encapsulation of soluble radioactive waste chloride salts containing radionuclides such as strontium, cesium and hazardous wastes such as barium so that they may be permanently stored without future threat to the environment. The process consists of contacting the salts containing the radionuclides and hazardous wastes with certain zeolites which have been found to ion exchange with the radionuclides and to occlude the chloride salts so that the resulting product is leach resistant.

US Patent:

56132409, Mar 18, 1997

Filed:

Jan 19, 1995

Appl. No.:

8/375141

Inventors:

Michele A. Lewis - Naperville IL
Candido Pereira - Lisle IL

Assignee:

The United States of America as represented by the United States
Department of Energy - Washington DC

International Classification:

G21F 900

US Classification:

588 11

Abstract:

A method for immobilizing waste chloride salts containing radionuclides and hazardous nuclear material for permanent disposal starting with a substantially dry zeolite and sufficient glass to form leach resistant sodalite with occluded radionuclides and hazardous nuclear material. The zeolite and glass are heated to a temperature up to about 1000. degree. K. to convert the zeolite to sodalite and thereafter maintained at a pressure and temperature sufficient to form a sodalite product near theoretical density. Pressure is used on the formed sodalite to produce the required density.