Effect of Mg 2+ Ions on Transport Properties in Molten Chloride Fast Reactor Fuels
Year: 2026
Type: article
Abstract: Molten chloride fast reactors (MCFRs) are emerging as a promising class of molten salt reactor (MSR) designs due to their ability to dissolve large amounts of major actinides while keeping low melting points and sustaining a hard neutron spectrum. In this context, understanding molten salt transport properties—such as viscosity and self-diffusivity—is essential for the design and optimisation of MSRs with efficient heat transfer characteristics. However, an important gap remains in the literature regarding transport properties in molten chlorides. In this work, we performed classical molecular dynamics (MD) simulations with the Polarisable Ion Model (PIM) to evaluate the viscosities and self-diffusion coefficients of molten NaCl–MgCl2–LaCl3, which was used in our previous work as a simulant for the ARAMIS-A reactor fuel. To validate the accuracy of our approach, calculated transport properties for the NaCl–LaCl3 binary system were benchmarked against capillary viscometry measurements from the literature and our own Pulsed-Field Gradient Nuclear Magnetic Resonance (PFG–NMR) experiments. Our study compares the roles of NaCl and MgCl2 on the transport properties of MCFR fuels. Interestingly, we observe that MgCl2 does not impact LaCl3-poor and LaCl3-rich melts in a similar way, due to the competition between the multivalent ions to attract chloride ions in their first shell and their ability to form cluster species.
Language: English
Subfield: Fluid Flow and Transfer Processes
Field: Chemical Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7128008864