The development of measurement methodologies to detect and monitor nuclear-relevant materials remains a consistent significant interest across the nuclear energy, nonproliferation, safeguards, forensics communities. Optical spectroscopy laser-produced plasmas is becoming an increasingly popular diagnostic technique measure radiological in field without sample preparation, where current capabilities encompass standoff, isotopically resolved phase-identifiable (e.g., UO UO[Formula: see text])...

Abstract Bench‐scale tests were performed to study an electrolytic reduction process that converts metal oxides in spent nuclear fuel metal. Crushed oxide was loaded into a permeable stainless steel basket and submerged molten salt electrolyte of LiCl–1 wt% Li2O at 650°C. An electrical current passed through the platinum wire, effecting formation oxygen gas on wire surface. Salt samples analyzed, extent fission product separation determined.

Thermodynamic and electrochemical properties of cerium in LiCl-KCl eutectic salt have been measured studied at different concentrations (0.5 – 4 wt%) temperatures (698 K 798 K) via both cyclic voltammetry (CV) impedance spectroscopy (EIS) techniques as a part developing fundamental understanding methodology materials detection accountability for pyroprocessing technology. CV experiments were performed to determine the diffusion coefficient apparent standard potential CeCl3 on tungsten...

Electrochemical and thermodynamic properties of Ce3+/Ce on liquid cadmium cathode (LCC) were investigated in LiCl-KCl salt at various temperatures. Cyclic voltammograms only attributing to reaction obtained by background subtraction method diffusion coefficients Ce the LCC determined temperatures ranging from 723 K 798 K. Furthermore, Ce-Cd intermetallic compound formations measured via an open circuit chronopotentiometry technique temperature 698 823 The linear dependence Gibbs free energy...

In the pyrochemical separation of used nuclear fuel (UNF), fission product, rare earth, and actinide chlorides accumulate in molten salt electrolyte over time. Measuring this composition near real-time is advantageous for operational efficiency, material accountability, safeguards. Laser-induced breakdown spectroscopy (LIBS) has been proposed demonstrated as a potential analytical approach LiCl–KCl salts. However, all studies conducted to date have static surface which can lead issues with...

In this current study, the molten salt aerosol–laser-induced breakdown spectroscopy (LIBS) system was used to measure uranium (U) content in a ternary UCl 3 –LiCl–KCl investigate and assess near real-time analytical approach for material safeguards accountability. Experiments were conducted using five different U concentrations determine figures of merit with respect U. analysis, three lines develop univariate calibration curves at 367.01 nm, 385.96 387.10 nm lines. The line had lowest limit...

Pyroprocessing of used nuclear fuel (UNF) has many advantages—including that it is proliferation resistant. However, as part the process, special materials accumulate in electrolyte salt and present material accountability safeguards concerns. The main motivation this work was to explore a laser-induced breakdown spectroscopy (LIBS) approach an online monitoring technique enhance pyroprocessing. In work, vacuum extraction method draw molten (CeCl 3 -GdCl -LiCl-KCl) up into 4 mm diameter...

Cl2/Cl− reference system was established with quartz cell where Cl2 gas trapped on a glassy carbon electrode surface allowing the thermodynamic equilibrium between and Cl− ions. Based reference, potential of Ag/AgCl evaluated at concentrations ranging from 0.00039 mole fraction AgCl to 1.0 temperatures 723 K 823 K. The measured values ranged −0.877 V −1.361 followed linear correlations against temperature concentration. However, pure showed slight upward in comparison other observed trends....

Laser-induced breakdown spectroscopy (LIBS) was used to detect and measure the concentrations of Ce Gd in aqueous aerosol solutions. A total 36 standards, with ranging from 100 parts per million (ppm) 10 000 ppm, were made explore relationship between them. In this study, a Collison nebulizer an argon carrier gas generate droplets. For each liquid sample, ten repetitions 200 laser shots recorded. The percent relative standard deviations (%RSD) on average 7.5% different sample repetitions....

Abstract A two‐site equilibrium model that previously only accommodated monovalent cations has been extended to include divalent and trivalent for ion exchange between zeolite‐A molten chloride salts, a process being considered concentrating nuclear fission products into high level waste forms. Equilibrium constants were determined by fitting the data sets Cs ternary salt (CsCl‐LiCl‐KCl), Rb (RbCl‐LiCl‐KCl), Na (NaCl‐LiCl‐KCl), Sr (SrCl 2 ‐LiCl‐KCl), U (UCl 3 ‐LiCl‐KCl). The results reveal...

The effect of temperature on the surface tension soluble and insoluble surfactants was investigated at an air−water interface. Equilibrium measurements were performed using Wilhelmy plate technique in which both concentration varied systematically. Insoluble (oleyl alcohol hemicyanine) (Triton X-100 sodium dodecyl sulfate (SDS)) used since they are commonly hydrodynamic experiments effects free dynamics studied. principal result this investigation is that above-mentioned decreases linearly...

The electrochemical processing of spent metallic nuclear fuel has been demonstrated by and is currently in operation at the Idaho National Laboratory (INL). At heart this process Mark-IV electrorefiner (ER). This involves anodic dissolution into a molten salt electrolyte along with simultaneous deposition pure uranium on solid cathode. allows fission products to be separated from processed an engineered waste form. A one-dimensional model ER begun developed. computations thus far have...

The electrochemical techniques including cyclic voltammetry (CV), open circuit potential (OCP), and impedance spectroscopy (EIS) were performed to understand fundamental behaviors of UCl3 in LiCl-KCl salt at concentrations ranging from 0.5 wt% 4 temperatures 723 K 798 K. In addition, the same measurements LiCl-KCl-UCl3-GdCl3 for evaluating effects GdCl3 co-existence on uranium properties. Diffusion coefficients (D) was calculated by measuring reduction peaks U3+/U CV experiments. values D...

This study provides a fundamental understanding of cold finger melt crystallization technique by exploring the heat and mass transfer processes separation. A series experiments were performed using simplified LiCl-CsCl system varying initial CsCl concentrations (1, 3, 5, 7.5 wt%), cooling rates (7.4, 9.8, 12.3, 14.9 L/min), separation times (5, 10, 15, 30 min). Results showed potential recycling rate 0.36 g/min with purity 0.33 wt% in LiCl. concentrated drip formation was found to decrease...

In this study, a diffusion-based kinetic model essential for design and operational analysis of spent nuclear fuel reduction has been developed. The considers the cathode side system to be rate limiting deals with diffusion lithium metal through basket loaded uranium oxide (UO2 or U3O8). Faraday’s law was implemented into observe electrochemical effect on model. Solutions different conditions are developed, detailed results presented. These solutions were compared against experimental bench...