Transpassive electrodissolution of depleted uranium in alkaline electrolytes

Technical Report · Sun Mar 01 04:00:00 EST 1998

DOI:https://doi.org/10.2172/650176· OSTI ID:650176

Weisbrod, K R; Schake, A R; Morgan, A N; Purdy, G M; Martinez, H E; Nelson, T O

To aid in removal of oralloy from the nuclear weapons stockpile, scientists at the Los Alamos National Laboratory Plutonium Facility are decontaminating oralloy parts by electrodissolution in neutral to alkaline electrolytes composed of sodium nitrate and sodium sulfate. To improve the process, electrodissolution experiments were performed with depleted uranium to understand the effects of various operating parameters. Sufficient precipitate was also produced to evaluate the feasibility of using ultrafiltration to separate the uranium oxide precipitates from the electrolyte before it enters the decontamination fixture. In preparation for the experiments, a potential-pH diagram for uranium was constructed from thermodynamic data for fully hydrated species. Electrodissolution in unstirred solutions showed that uranium dissolution forms two layers, an acidic bottom layer rich in uranium and an alkaline upper layer. Under stirred conditions results are consistent with the formation of a yellow precipitate of composition UO{sub 3}{center_dot}2H{sub 2}O, a six electron process. Amperometric experiments showed that current efficiency remained near 100% over a wide range of electrolytes, electrolyte concentrations, pH, and stirring conditions.

• Research Organization: Los Alamos National Lab., NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 650176
• Report Number(s): LA--13416-MS; ON: DE98004419
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
40 CHEMISTRY
DEPLETED URANIUM
DISSOLUTION
ELECTROLYSIS
ENRICHED URANIUM
EXPERIMENTAL DATA
HYDRATES
NUCLEAR WEAPONS DISMANTLEMENT
URANIUM OXIDES