skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Process for converting sodium nitrate-containing, caustic liquid radioactive wastes to solid insoluble products

Abstract

A method for converting sodium nitrate-containing, caustic, radioactive wastes to a solid, relatively insoluble, thermally stable form is provided and comprises the steps of reacting powdered aluminum silicate clay, e.g., kaolin, bentonite, dickite, halloysite, pyrophyllite, etc., with the sodium nitrate-containing radioactive wastes which have a caustic concentration of about 3 to 7 M at a temperature of 30.degree. C to 100.degree. C to thereby entrap the dissolved radioactive salts in the aluminosilicate matrix. In one embodiment the sodium nitrate-containing, caustic, radioactive liquid waste, such as neutralized Purex-type waste, or salts or oxide produced by evaporation or calcination of these liquid wastes (e.g., anhydrous salt cake) is converted at a temperature within the range of 30.degree. C to 100.degree. C to the solid mineral form-cancrinite having an approximate chemical formula 2(NaAlSiO.sub.4) .sup.. xSalt.sup.. y H.sub.2 O with x = 0.52 and y = 0.68 when the entrapped salt is NaNO.sub.3. In another embodiment the sodium nitrate-containing, caustic, radioactive liquid is reacted with the powdered aluminum silicate clay at a temperature within the range of 30.degree. C to 100.degree. C, the resulting reaction product is air dried eitheras loose powder or molded shapes (e.g., bricks) and then fired at a temperature ofmore » at least 600.degree. C to form the solid mineral form-nepheline which has the approximate chemical formula of NaAlSiO.sub.4. The leach rate of the entrapped radioactive salts with distilled water is reduced essentially to that of the aluminosilicate lattice which is very low, e.g., in the range of 10.sup.-.sup.2 to 10.sup.-.sup.4 g/cm.sup.2 -- day for cancrinite and 10.sup.-.sup.3 to 10.sup.-.sup.5 g/cm.sup.2 -- day for nepheline.« less

Inventors:
 [1];  [1]
  1. (Richland, WA)
Publication Date:
Research Org.:
Atlantic Richfield Hanford Co., Richland, Wash. (USA)
OSTI Identifier:
862848
Patent Number(s):
US 4028265
Assignee:
United States of America as represented by United States Energy (Washington, DC) OSTI
DOE Contract Number:  
AT(45-1)-2130
Resource Type:
Patent
Country of Publication:
United States
Language:
English
Subject:
process; converting; sodium; nitrate-containing; caustic; liquid; radioactive; wastes; solid; insoluble; products; method; relatively; thermally; stable; form; provided; comprises; steps; reacting; powdered; aluminum; silicate; clay; kaolin; bentonite; dickite; halloysite; pyrophyllite; etc; concentration; temperature; 30; degree; 100; entrap; dissolved; salts; aluminosilicate; matrix; embodiment; waste; neutralized; purex-type; oxide; produced; evaporation; calcination; anhydrous; salt; cake; converted; range; mineral; form-cancrinite; approximate; chemical; formula; naalsio; xsalt; 52; 68; entrapped; nano; reacted; resulting; reaction; product; air; dried; eitheras; loose; powder; molded; shapes; bricks; fired; 600; form-nepheline; leach; rate; distilled; water; reduced; essentially; lattice; 10; cm; cancrinite; nepheline; radioactive liquid; stable form; liquid wastes; liquid radioactive; sodium nitrate-containing; reaction product; radioactive waste; liquid waste; thermally stable; radioactive wastes; chemical formula; sodium nitrate; containing radioactive; resulting reaction; salt cake; solid mineral; powdered aluminum; air dried; silicate clay; distilled water; silicate matrix; active liquid; oxide produced; radioactive salt; soluble products; loose powder; converting sodium; /588/976/

Citation Formats

Barney, Gary S., and Brownell, Lloyd E. Process for converting sodium nitrate-containing, caustic liquid radioactive wastes to solid insoluble products. United States: N. p., 1977. Web.
Barney, Gary S., & Brownell, Lloyd E. Process for converting sodium nitrate-containing, caustic liquid radioactive wastes to solid insoluble products. United States.
Barney, Gary S., and Brownell, Lloyd E. Sat . "Process for converting sodium nitrate-containing, caustic liquid radioactive wastes to solid insoluble products". United States. https://www.osti.gov/servlets/purl/862848.
@article{osti_862848,
title = {Process for converting sodium nitrate-containing, caustic liquid radioactive wastes to solid insoluble products},
author = {Barney, Gary S. and Brownell, Lloyd E.},
abstractNote = {A method for converting sodium nitrate-containing, caustic, radioactive wastes to a solid, relatively insoluble, thermally stable form is provided and comprises the steps of reacting powdered aluminum silicate clay, e.g., kaolin, bentonite, dickite, halloysite, pyrophyllite, etc., with the sodium nitrate-containing radioactive wastes which have a caustic concentration of about 3 to 7 M at a temperature of 30.degree. C to 100.degree. C to thereby entrap the dissolved radioactive salts in the aluminosilicate matrix. In one embodiment the sodium nitrate-containing, caustic, radioactive liquid waste, such as neutralized Purex-type waste, or salts or oxide produced by evaporation or calcination of these liquid wastes (e.g., anhydrous salt cake) is converted at a temperature within the range of 30.degree. C to 100.degree. C to the solid mineral form-cancrinite having an approximate chemical formula 2(NaAlSiO.sub.4) .sup.. xSalt.sup.. y H.sub.2 O with x = 0.52 and y = 0.68 when the entrapped salt is NaNO.sub.3. In another embodiment the sodium nitrate-containing, caustic, radioactive liquid is reacted with the powdered aluminum silicate clay at a temperature within the range of 30.degree. C to 100.degree. C, the resulting reaction product is air dried eitheras loose powder or molded shapes (e.g., bricks) and then fired at a temperature of at least 600.degree. C to form the solid mineral form-nepheline which has the approximate chemical formula of NaAlSiO.sub.4. The leach rate of the entrapped radioactive salts with distilled water is reduced essentially to that of the aluminosilicate lattice which is very low, e.g., in the range of 10.sup.-.sup.2 to 10.sup.-.sup.4 g/cm.sup.2 -- day for cancrinite and 10.sup.-.sup.3 to 10.sup.-.sup.5 g/cm.sup.2 -- day for nepheline.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {1977},
month = {1}
}

Patent:

Save / Share: