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Approach of the Molten Salt Chemistry for Aluminium Production: High Temperature NMR Measurements, Molecular Dynamics and DFT Calculations

  • Kelly Machado
  • Didier Zanghi
  • Vincent Sarou-Kanian
  • Sylvian Cadars
  • Mario Burbano
  • Mathieu Salanne
  • Catherine Bessada
Conference paper

Abstract

In aluminum production, the electrolyte is a molten fluorides mixture typically around 1000°C. In order to have a better understanding of the industrial process, it is necessary to have a model which will describe the molten salts on a wide range of compositions and temperatures, to accurately cover all the combinations that may be encountered in an operating electrolysis vessel. The aim of this study is to describe the speciation in the electrolyte in terms of anionic species in the bulk materials far from electrodes. To determine the speciation in situ at high temperature in the absence of an electrical field, we develop an original approach combining experimental methods such as Nuclear Magnetic Resonance spectroscopy (NMR) at high temperature with Molecular Dynamics (MD) simulation coupled with first principle calculations based on Density Functional Theory (DFT). This approach allows the calculation of NMR parameters and the comparison with the experimental ones. It will be provide an additional validation and constraint of the model used for MD. We test this approach on the model NaF-AlF3 system.

Keywords

NaF-AlF3 high temperature NMR chemical shifts anionic species molecular dynamic functional theory of density (DFT) Polarizable Ion Model (PIM) 

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Copyright information

© TMS (The Minerals, Metals & Materials Society) 2016

Authors and Affiliations

  • Kelly Machado
    • 1
  • Didier Zanghi
    • 1
  • Vincent Sarou-Kanian
    • 1
  • Sylvian Cadars
    • 2
  • Mario Burbano
    • 3
  • Mathieu Salanne
    • 3
  • Catherine Bessada
    • 1
  1. 1.CEMHTI (Conditions Extrême Matériaux Haute Température et Irradiation) CNRSUniversité OrléansOrléansFrance
  2. 2.IMN (Institut des Materiaux Jean Rouxel) CNRSUniversité de NantesNantesFrance
  3. 3.PHENIX CNRSUPMC (University Pierre et Marie Curie)ParisFrance

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