Nuclear waste encapsulation in borosilicate glass by chemical polymerization
First Claim
1. A method of encapsulating an aqueous solution of nuclear waste, comprising:
- (A) adjusting the pH of said solution of nuclear waste to about 4 to about 6;
(B) preparing a composition in an alcohol which consists essentially of;
(1) about 1 to about 99% by weight of a silicon compound having the general formula Si(OR)4 where each R is independently selected from alkyl to C6 ; and
(2) about 1 to about 99% by weight of a boron compound having the general formula B(OR)3 where each R is independently selected from alkyl to C6, said composition being partially hydrolyzed;
(C) adjusting the pH of said composition to about the pH of said solution of nuclear waste;
(D) drying said composition to about 50 to about 75% of its original volume;
(E) mixing together up to about 30% by weight of said solution of nuclear waste with said composition, based on total weight, to form a gel;
(F) drying the mixture at a temperature between room temperature and the boiling point of said alcohol;
(G) heating said mixture at up to 500°
C.;
(H) consolidating said mixture by(1) warm pressing at about 400 to about 800°
C. at about 40,000 to about 100,000 psi;
or(2) melting said mixture at about 700°
to about 1150°
C.
3 Assignments
0 Petitions
Accused Products
Abstract
Disclosed is a process for containing a solution of nuclear waste, where the nuclear waste is at least 10% sodium or nitrate. A composition is prepared in an alcohol of about 1 to about 99% of a silicon alkoxide and about 1 to about 99% of a boron alkoxide. The pH of the nuclear waste solution is adjusted to about 4 to about 6 and the pH of the composition is adjusted to match. The composition is dried to about 50 to about 75% of its original volume and is mixed with up to about 30% of the solution of nuclear waste, thereby forming a gel. The mixture is dried and heated at up to about 500° C. Finally, it is consolidated either by warm pressing at about 400° to about 800° C. at about 40,000 to about 100,000 psi, or by melting at about 700° to about 1150° C.
26 Citations
11 Claims
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1. A method of encapsulating an aqueous solution of nuclear waste, comprising:
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(A) adjusting the pH of said solution of nuclear waste to about 4 to about 6; (B) preparing a composition in an alcohol which consists essentially of; (1) about 1 to about 99% by weight of a silicon compound having the general formula Si(OR)4 where each R is independently selected from alkyl to C6 ; and (2) about 1 to about 99% by weight of a boron compound having the general formula B(OR)3 where each R is independently selected from alkyl to C6, said composition being partially hydrolyzed; (C) adjusting the pH of said composition to about the pH of said solution of nuclear waste; (D) drying said composition to about 50 to about 75% of its original volume; (E) mixing together up to about 30% by weight of said solution of nuclear waste with said composition, based on total weight, to form a gel; (F) drying the mixture at a temperature between room temperature and the boiling point of said alcohol; (G) heating said mixture at up to 500°
C.;(H) consolidating said mixture by (1) warm pressing at about 400 to about 800°
C. at about 40,000 to about 100,000 psi;
or(2) melting said mixture at about 700°
to about 1150°
C. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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Specification
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- Resources
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Current AssigneeWestinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
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Original AssigneeWestinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
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InventorsYoldas, Bulent E., Chickering, Ronald W., Neuman, Bruce H.
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Primary Examiner(s)Kyle, Deborah L.
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Application NumberUS06/176,738Time in Patent Office1,233 DaysField of Search252/629, 501/12US Class Current588/12CPC Class CodesC03C 1/002 Use of waste materials, e.g...C03C 1/006 to produce glass through we...G21F 9/162 in an inorganic matrix, e.g...G21F 9/305 Glass or glass like matrix ...Y10S 65/901 Liquid phase reaction process
