title: Potentiometric Sensor for Real-Time Monitoring of Multivalent Ion
 Concentrations in Molten Salt
creator: Zink, Peter A.
creator: Jue, Jan-Fong
creator: Serrano, Brenda E.
creator: Fredrickson, Guy L.
creator: Cowan, Ben F.
creator: Herrmann, Steven D.
creator: Li, Shelly X.
contributor: United States. National Nuclear Security Administration.
publisher: Idaho National Laboratory
date: 2010-07-01
language: English
description: Electrorefining of spent metallic nuclear fuel in high temperature
 molten salt systems is a core technology in pyroprocessing, which in turn
 plays a critical role in the development of advanced fuel cycle technologies.
 In electrorefining, spent nuclear fuel is treated electrochemically in order
 to effect separations between uranium, noble metals, and active metals, which
 include the transuranics. The accumulation of active metals in a lithium
 chloride-potassium chloride (LiCl-KCl) eutectic molten salt electrolyte occurs
 at the expense of the UCl3-oxidant concentration in the electrolyte, which
 must be periodically replenished. Our interests lie with the accumulation of
 active metals in the molten salt electrolyte. The real-time monitoring of
 actinide concentrations in the molten salt electrolyte is highly desirable for
 controlling electrochemical operations and assuring materials control and
 accountancy. However, real-time monitoring is not possible with current
 methods for sampling and chemical analysis. A new solid-state electrochemical
 sensor is being developed for real-time monitoring of actinide ion
 concentrations in a molten salt electrorefiner. The ultimate function of the
 sensor is to monitor plutonium concentrations during electrorefining
 operations, but in this work gadolinium was employed as a surrogate material
 for plutonium. In a parametric study, polycrystalline sodium beta double-prime
 alumina (Na-ß?-alumina) discs and tubes were subject to vapor-phase exchange
 with gadolinium ions (Gd3+) using a gadolinium chloride salt (GdCl3) as a
 precursor to produce gadolinium beta double-prime alumina (Gd-ß?-alumina)
 samples. Electrochemical impedance spectroscopy and microstructural analysis
 were performed on the ion-exchanged discs to determine the relationship
 between ion exchange and Gd3+ ion conductivity. The ion-exchanged tubes were
 configured as potentiometric sensors in order to monitor real-time Gd3+ ion
 concentrations in mixtures of gadolinium chloride (GdCl3) in LiCl-KCl eutectic
 molten salts through measurement of the potential difference between a
 reference and working electrode.
subject: Fuel Cycle
subject: Electrolytes
subject: Gadolinium Ions
subject: Actinide
subject: Multivalent
subject: Eutectics
subject: 98 Nuclear Disarmament, Safeguards, And Physical Protection
subject: Pyroprocessing
subject: Uranium Actinide
subject: Gadolinium Chlorides
subject: Spectroscopy
subject: Ion Exchange
subject: Plutonium
subject: Electrorefining
subject: Ceramic
subject: Actinides
subject: Sampling
subject: 11 Nuclear Fuel Cycle And Fuel Materials
subject: Nuclear Fuels
subject: Gadolinium
subject: Safeguards
subject: Chemical Analysis
subject: Chlorides
subject: Monitoring
subject: Sodium
subject: Molten Salts
subject: Lithium
subject: Sensor
source: INMM 51st Annual Meeting,Baltimore, MD USA,07/11/2010,07/15/2010
type: Article
format: Text
identifier: rep-no: INL/CON-10-17752
identifier: grantno: DE-AC07-05ID14517
identifier: osti: 1000527
identifier: https://digital.library.unt.edu/ark:/67531/metadc830792/
identifier: ark: ark:/67531/metadc830792