Light Metals 2014 pp 1239-1244 | Cite as

Interaction of Sodium Vapor and Graphite Studied by Thermogravimetric Analysis

Chapter

Abstract

Intercalation of sodium in carbon materials is of paramount importance for the Hall-Héroult process. The interaction of sodium and graphite has been investigated for decades, but despite considerable efforts, the transport and nature of sodium in carbon materials are still poorly understood. Here we report on a study of the interaction between graphite and sodium vapor by thermogravimetric analysis. A graphitized carbon material was exposed to sodium vapor, and the equilibration of sodium uptake in the carbon material was monitored. The kinetics of the sodium uptake is discussed with respect to surface adsorption, bulk diffusion and the solid solubility of sodium in graphite. The kinetics of the reaction was analyzed with support from finite element method simulations. Finally, recent density functional theory simulations of sodium intercalation compounds are presented, demonstrating the low thermodynamic stability of such sodium intercalation compounds reflecting the low reactivity of sodium with carbon.

Keywords

Aluminum Electrolysis Graphite Thermogravimetry Sodium Diffusion DFT Calculation 
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Copyright information

© TMS (The Minerals, Metals & Materials Society) 2014

Authors and Affiliations

  • Z. Wang
    • 1
  • A. P. Ratvik
    • 2
  • E. Skybakmoen
    • 2
  • T. Grande
    • 1
  1. 1.Department of Materials Science and EngineeringNorwegian University of Science and TechnologyTrondheimNorway
  2. 2.SINTEF Materials and ChemistryTrondheimNorway

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