Method for the manufacture of (U,Pu)O.sub.2 mixed crystals
AssigneeAlkem GmbH
InventorsWolf-Gunther Druckenbrodt, Siegfried Baumann, Roland Krause, Wolfgang Stoll
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Abstract
Manufacture of uranium/plutonium oxide mixed crystals soluble in nitric acid in which a solution of uranium nitrate and plutonium nitrate are oxidized to cause the plutonium to reach valence VI. The oxidized solution is admixed with ammonium carbonate, oxalate or carbamate and the pH adjusted to 8.1 to 8.5 to precipitate an ammonium uranyl plutonyl carbonate, oxalate or carbamate. The precipitate is calcined to uranium/plutonium oxide.
Claims17
Method for the manufacture of uranium/plutonium oxide mixed crystals soluble in 10 molar nitric acid as a preliminary stage for the fabrication of sintered nuclear fuel bodies with uranium-and plutonium-containing materials, which comprises
- (a) oxidizing a mixture of uranyl nitrate and plutonium nitrate in aqueous solution to cause the plutonium to reach a stage of oxidation with a valence VI,
- (b) admixing the oxidized solution with an aqueous solution of a salt selected from the group consisting of ammonium carbonate, ammonium oxalate and ammonium carbamate and adjusting the pH of the admixture to 8.1-8.5 by adding NH.sub.3 as well as CO.sub.2 while maintaining a temperature of about 45.degree. to 60.degree. C. to precipitate an ammonium uranyl plutonyl carbonate, oxalate or carbamate depending on the use the particular salt selected from the group consisting of ammonium carbonate, ammonium oxalate and ammonium carbamate,
- (c) calcining the precipitate in a reducing atmosphere at about 300.degree.-700.degree. C. to produce a uranium-plutonium oxide, and
- (d) adjusting the uranium-plutonium oxide to a desired oxygen/metal ratio.
Method of producing compounds having the general formula
- (NH.sub.4).sup.+.sub.n [(U/Pu)O.sub.2 ].sup.2+.sub.m (X).sub.i.sup.2-
- wherein X represents a member of the group consisting of CO.sub.3, (COO).sub.2 and NH.sub.2 COO, and wherein n is a numeral from 0 to 6, m means one of the numbers one and two, and i is a numeral from 1 to 5, which comprises oxidizing solution of uranyl nitrate and plutonium nitrate to cause the plutonium to be oxidized to valence VI, admixing the oxidized solution with a salt selected from the group consisting of ammonium carbonate, ammonium oxalate and ammonium carbamate to produce a precipitate having said formula, and separating said precipitate.
Method of producing compounds having the formula
- (NH.sub.4).sub.n [(U/Pu) O.sub.2 ](X).sub.3
- wherein X represents a member of the group consisting of CO.sub.3, (COO).sub.2 and NH.sub.2 COO, and wherein n is a numeral from 0 to 4, which comprises oxidizing a solution of uranyl nitrate and plutonium nitrate to cause the plutonium to be oxidized to valence VI, admixing the oxidized solution with a salt selected from the group consisting of ammonium carbonate, ammonium oxalate and ammonium carbamate, maintaining a temperature of about 45.degree. to 60.degree. C. and a pH of 8.1 to 8.5 to produce a precipitate having said formula, and separating said precipitate.
Dependencies are inferred from the claim text.