Investigating Current Efficiency of Aluminum Electrolysis in NaF-KF-AlF3 System

  • Huanhuan Ma
  • Jilai Xue
  • Jigang Li
  • Yanan Zhang
Chapter

Abstract

Existing indusial aluminum electrolysis is operated at about 950 °C. In this work, NaF-KF-AlF3 based electrolytes were used at lower temperatures and the current efficiency of laboratory aluminum electrolysis was measured by mass loss method. The effects of KF addition, electrolyte compositions (cryolite ratio 1.8–2.5), and temperatures (890–960 °C) were studied in a laboratory cell with carbon electrodes. The obtained results suggest that alternative technology of lower temperature electrolysis has to overcome some problems to reach the operational goal in energy savings and production efficiency.

Keywords

Aluminum electrolysis current efficiency KF addition 
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Copyright information

© TMS (The Minerals, Metals & Materials Society) 2013

Authors and Affiliations

  • Huanhuan Ma
    • 1
  • Jilai Xue
    • 1
  • Jigang Li
    • 1
  • Yanan Zhang
    • 1
  1. 1.School of Metallurgical and Ecological EngineeringUniversity of Science and Technology BeijingBeijingChina

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