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Title: Synthesis of Uranium Trichloride for the Pyrometallurgical Processing of Used Nuclear Fuel

Abstract

The pyroprocessing of used nuclear fuel via electrorefining requires the continued addition of uranium trichloride to sustain operations. Uranium trichloride is utilized as an oxidant in the system to allow separation of uranium metal from the minor actinides and fission products. The inventory of uranium trichloride had diminished to a point that production was necessary to continue electrorefiner operations. Following initial experimentation, cupric chloride was chosen as a reactant with uranium metal to synthesize uranium trichloride. Despite the variability in equipment and charge characteristics, uranium trichloride was produced in sufficient quantities to maintain operations in the electrorefiner. The results and conclusions from several experiments are presented along with a set of optimized operating conditions for the synthesis of uranium trichloride.

Authors:
; ;
Publication Date:
Research Org.:
Idaho National Laboratory (INL)
Sponsoring Org.:
DOE - NE
OSTI Identifier:
1045491
Report Number(s):
INL/CON-10-20111
TRN: US1203624
DOE Contract Number:
DE-AC07-05ID14517
Resource Type:
Conference
Resource Relation:
Conference: Fray International Symposium on Molten Salts and Ionic Liquids 2011,Cancun, Mexico,11/27/2011,12/01/2011
Country of Publication:
United States
Language:
English
Subject:
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS; ACTINIDES; CHLORIDES; ELECTROREFINING; FISSION PRODUCTS; MOLTEN SALTS; NUCLEAR FUELS; OXIDIZERS; PROCESSING; PRODUCTION; SYNTHESIS; URANIUM; SPENT FUELS; Pyrometallurgical Processing; Uranium Trichloride

Citation Formats

B.R. Westphal, J.C. Price, and R.D. Mariani. Synthesis of Uranium Trichloride for the Pyrometallurgical Processing of Used Nuclear Fuel. United States: N. p., 2011. Web.
B.R. Westphal, J.C. Price, & R.D. Mariani. Synthesis of Uranium Trichloride for the Pyrometallurgical Processing of Used Nuclear Fuel. United States.
B.R. Westphal, J.C. Price, and R.D. Mariani. Tue . "Synthesis of Uranium Trichloride for the Pyrometallurgical Processing of Used Nuclear Fuel". United States. doi:. https://www.osti.gov/servlets/purl/1045491.
@article{osti_1045491,
title = {Synthesis of Uranium Trichloride for the Pyrometallurgical Processing of Used Nuclear Fuel},
author = {B.R. Westphal and J.C. Price and R.D. Mariani},
abstractNote = {The pyroprocessing of used nuclear fuel via electrorefining requires the continued addition of uranium trichloride to sustain operations. Uranium trichloride is utilized as an oxidant in the system to allow separation of uranium metal from the minor actinides and fission products. The inventory of uranium trichloride had diminished to a point that production was necessary to continue electrorefiner operations. Following initial experimentation, cupric chloride was chosen as a reactant with uranium metal to synthesize uranium trichloride. Despite the variability in equipment and charge characteristics, uranium trichloride was produced in sufficient quantities to maintain operations in the electrorefiner. The results and conclusions from several experiments are presented along with a set of optimized operating conditions for the synthesis of uranium trichloride.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Nov 01 00:00:00 EDT 2011},
month = {Tue Nov 01 00:00:00 EDT 2011}
}

Conference:
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  • Recovery of uranium from the Mk-IV and Mk-V electrorefiner vessels containing a LiCl/KCl eutectic salt has been on-going for 14 and 12 years, respectively, during the pyrometallurgical processing of used nuclear fuel. Although austenitic stainless steels are typically utilized for LiCl/KCl salt systems, the presence of cadmium in the Mk-IV electrorefiner dictates an alternate material. A 2.25Cr-1Mo alloy (ASME SA-387) was chosen due to the absence of nickel in the alloy which has a considerable solubility in cadmium. Using the transition metal impurities (iron, chromium, nickel, molybdenum, and manganese) in the electrorefined uranium products, an algorithm was developed to derivemore » values for the contribution of the transition metals from the various input sources. Weight loss and corrosion rate data for the Mk-V electrorefiner vessel were then generated based on the transition metal impurities in the uranium products. To date, the corrosion rate of the 2.25Cr-1Mo alloy in LiCl/KCl eutectic is outstanding assuming uniform (i.e. non-localized) conditions.« less
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