A comparison of actinide halides for use in molten salt reactor fuels

Faure, Bastien; Kooyman, T.

doi:10.1016/j.pnucene.2021.104082

Cited by 11 publications

(4 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Actinide halides ([AnX n ] q − , X = halide) have attracted the scientific community’s attention due to their use in the nuclear industry, primarily for isotope enrichment, and are among the most extensively exploited molecular units within the domain of actinide chemistry. − Furthermore, actinide halides are widely used in actinide separation processes and also have significant applications in non-aqueous transuranic chemistry. , [AnO 2 Cl 2 ] and [AnCl 6 ] 2– are two dominating structural motifs identified for An(VI) and An(IV) chlorides, respectively. − For example, [UO 2 Cl 2 ] and [PuO 2 Cl 2 ] have been characterized both in solution as well as in the solid state . Similarly, [UCl 6 ] 2– , [NpCl 6 ] 2– , and [PuCl 6 ] 2– have been isolated and explored in the literature. ,− Moreover, the octahedral ligand environment in [AnCl 6 ] 2– provides a suitable platform to examine the properties of actinides and compare them with transition metals in a similar coordination environment. ,, The presence of non-aquo inner sphere ligands limits the hydrolyzation of An(IV) species; therefore, there is a fundamental need to understand and control their speciation, especially toward the formation of intermediates capable of undergoing olation or oxolation reactions.…”

Section: Introductionsupporting

confidence: 84%

Aqueous Speciation of Tetravalent Actinides in the Presence of Chloride and Nitrate Ligands

Bhattacharjee

Miró

2022

Inorg. Chem.

View full text Add to dashboard Cite

Speciation of hexachloride tetravalent uranium, neptunium, and plutonium species in aqueous media has been investigated using density functional theory in the presence of inner sphere ligands such as chloride, nitrate, and solvent molecules. All possible structures with the formula [An IV (Cl) x (H 2 O) y (NO 3 ) z ] 4−x−z (An = U, Np, and Pu; x = 0−6, y = 0−8, and z = 0−6) were considered to explore the speciation chemical space of each actinide. The nature of the mixed-ligand complexes present in solution is controlled by the concentration of free ligands in solution. A low chloride concentration is suitable to drive the speciation away from the highly thermodynamically stable hexachloride species. Furthermore, the formation of dimeric species can proceed through both olation and oxolation mechanisms. Oxolation is preferred for monomers that contain fewer water ligands, while olation becomes favorable for complexes with more water ligands.

show abstract

Section: Introductionsupporting

confidence: 84%

Aqueous Speciation of Tetravalent Actinides in the Presence of Chloride and Nitrate Ligands

Bhattacharjee

Miró

2022

Inorg. Chem.

View full text Add to dashboard Cite

show abstract

“…Actinyl halide chemistry is of relevance for understanding actinide behavior in, for example, molten salt nuclear reactor systems and long-term stewardship of spent nuclear fuel. − Uranyl fluoride phases are particularly important considering the roles of compounds such as uranium hexafluoride (UF 6 ), uranium tetrafluoride (UF 4 ), and uranyl fluoride (UO 2 F 2 ) as vital intermediates in the conversion, enrichment, and fuel fabrication steps within the nuclear fuel cycle. , However, in the solid state, the chemistry of uranyl halides has been dominated by chloride and bromide phases, owing largely to their ease of synthesis and the platform they provide for studying the molecular assembly and electronic structure. In brief, preparation from high-halide, low-pH aqueous media generates reproducible [UO 2 X 4 ] 2– anions (X = Cl or Br) for directed assembly with various organic cations, often assisted with noncovalent interactions (NCIs) such as halogen or hydrogen bonding. , …”

Section: Introductionmentioning

confidence: 99%

Structural, Spectroscopic, and Computational Analysis of Halogen- and Hydrogen-Bonding Effects within a Series of Uranyl Fluorides with 4-Halopyridinium

Decoteau,

Raghavan,

Cahill

2024

Inorg. Chem.

View full text Add to dashboard Cite

Reported are the syntheses and characterization of five compounds containing one-dimensional uranyl fluoride chains charge balanced by 4-X-pyridinium (X = H, F, Cl, Br, I) cations. Structural analysis reveals molecular assembly via noncovalent interactions in the second coordination sphere with the X•••O yl interaction distances ranging from 2.987(7) to 3.142(3) Å, all of which are less than or close to the sum of the van der Waals radii. These interactions were probed via luminescence and Raman spectroscopy, where the latter indicates slight differences in the U�O symmetric stretches as a consequence of U�O in-phase and out-of-phase Raman-active stretches. The decrease in the X•••O yl sum of the van der Waals overlap between comparable compounds within the series manifests as a red-shifting trend among the Raman symmetric stretches. Computational density functional theory (DFT)-based frequency, electrostatic potential surfaces (ESPs), and natural bonding orbital (NBO) methods support the observed Raman spectroscopic features and provide a comprehensive rationale for assembly.

show abstract

“…The first MSR by Oak Ridge National Laboratory (ORNL), named the Molten Salt Reactor Experiment (MSRE), received a positive response after operating for approximately four years [6,7]. The reactor used fluoride-fueled salt and graphite as moderators, which is considered a successful demonstration of the potential of MSR technology [8]. In 1971, ORNL developed the MSRE into a molten salt breeder reactor (MSBR).…”

Section: Introductionmentioning

confidence: 99%

Numerical Simulation of the Effect of Molten Salt Channel Number on Temperature Distribution in the Molten Salt Core Reactor

Dwiyulianti,

Yonanda,

Zulfalina

et al. 2024

J. Phys.: Conf. Ser.

View full text Add to dashboard Cite

A critical aspect in the design of a nuclear reactor that needs to be considered is thermal analysis. This parameter relates to molten salt circulation, which serves as a fuel, and coolant in Molten Salt Reactor (MSR) core reactors. This study simulates the temperature distribution performance of the MSR core by considering the effect of the number of molten salt channels with inlet temperature variations. Knowing the temperature distribution will predict the characteristics of heat transfer in the form of natural convection for the survival of the reactor. The reactor used a Molten Salt Breeder Reactor (MSBR) design developed by Oak Ridge National Laboratory (ORNL). The Ansys software was used to simulate a 3D model under steady-state conditions. The geometry was divided into two regions: solid (graphite material) and fluid (molten salt). The thickness of the moderator and radius of the molten salt channel were 0.0508 and 0.0208 m, respectively. The moderator height was 1.98 m. The number of molten salt channels varied up to four. The results showed a temperature difference of 9 to 15 K when the channel increased from one to four at 839 K inlet temperature.

show abstract

A comparison of actinide halides for use in molten salt reactor fuels

Cited by 11 publications

References 11 publications

Aqueous Speciation of Tetravalent Actinides in the Presence of Chloride and Nitrate Ligands

Aqueous Speciation of Tetravalent Actinides in the Presence of Chloride and Nitrate Ligands

Structural, Spectroscopic, and Computational Analysis of Halogen- and Hydrogen-Bonding Effects within a Series of Uranyl Fluorides with 4-Halopyridinium

Numerical Simulation of the Effect of Molten Salt Channel Number on Temperature Distribution in the Molten Salt Core Reactor

Contact Info

Product

Resources

About