LABORATORY DEVELOPMENT OF THE SULFEX PROCESS FOR THE DISSOLUTION OF CONSOLIDATED EDISON POWER REACTOR FUEL
Flowsheets given for dissolution of Consolidated Edison power reactor fuel, 96% ThO/sub 2/ --4% UO/sub 2/ sintered pellets clad in type 304L stainless steel, include removal of the stainless steel cladding with a 200% stoichiometric excess of boiling 4 or 6 M H/sub 2/SO/sub 4/. The ThC/sub 2/--UO/sub 2/ core is then dissolved in boiling 13 M HNO/sub 3/--0.04 M NaF--0.04 M Al(NO/sub 3/)/sub 3/ . Essentially complete dissolution of the stainless steel requires about 6 hr in the preferred reagent 6 M R/sub 2/SO/sub 4/; only about 80% is dissolved in 6 hr with 4 M H/sub 2/SO/sub 4/. Uranium and thorium losses to the decladding solution were, in general, less than 0.2 and 0.1%, respectively. After decladding, about 93% of the core is dissolved in 6 to 7 hr when a 200% stoichiometric excess of dissolvent is used; the resulting solution is 1 M in thorium. The ThO/sub 2/--UO/sub 2/ heel can be dissolved immediately in about 3 br in fresh dissolver solution, or can remain through subsequent decladding steps. Aluminum nitrate added to the core dissolver solution to inhibit corrosion does not affect the pellet dissolution rate at concentrations below 0.1 M. The solubilities of the neutron poisons boron and cadn ium in process solutions were determined Beric acid solubility was 0.2 to 0.4 M in most solutions; that of cadmium was 0.2 to 1.2 M. (auth)
- Research Organization:
- Oak Ridge National Lab., Tenn.
- DOE Contract Number:
- W-7405-ENG-26
- NSA Number:
- NSA-14-000258
- OSTI ID:
- 4202003
- Report Number(s):
- ORNL-2714
- Country of Publication:
- United States
- Language:
- English
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