2015-Sustainable Industrial Processing Summit
SIPS 2015 Volume 7: Ionic Liquids & Energy Production
| Editors: | Kongoli F, Gaune-Escard M, Mauntz M, Rubinstein J, Dodds H.L. |
| Publisher: | Flogen Star OUTREACH |
| Publication Year: | 2015 |
| Pages: | 310 pages |
| ISBN: | 978-1-987820-30-0 |
| ISSN: | 2291-1227 (Metals and Materials Processing in a Clean Environment Series) |
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Electrical Conductivity of Cryolite - Based System With Low Melting Temperature
Piotr Palimaka1; Stanislaw Pietrzyk1;1AGH UNIVERSITY OF SCIENCE AND TECHNOLOGY, Krakow, Poland;
Type of Paper: Regular
Id Paper: 93
Topic: 13
Abstract:
In order to reduce the high temperature aluminum electrolysis process it is proposed to apply so-called low-melting electrolytes. It is considered that KF-AlF3-based solutions are promising electrolytes in this process. In this work, the electrical conductivity of low-melting electrolytes (nKF/nAlF3=1.3-1.7) with Al2O3 (4 mas.%), NaF (2-6 mas.%) and LiF (2-6 mas.%) additives was investigated using BN tube type cell. The melts were measured by continuously varying cell constant (CVCC) method. AC - techniques with a sine wave signal with 10mV amplitude in the high frequency range (5-100 kHz) were applied. Electrical conductivity of aqueous solution of KCl, molten KCl and Na3AlF6 was measured to check the measuring method. The results prove that the method is reliable and accurate. The conductivity of investigated electrolytes was found to vary linearly with temperature. The activation energy of conductance was calculated based on Arrhenius equation. The electrical conductivity is decreased with Al2O3 and increased with NaF and LiF additions.
Keywords:
Conductivity; Electrolysis; Moltensalt;References:
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