Abstract
The extent to which the carbon cathode is wetted by molten electrolyte or molten aluminium metal is important for understanding the cathode wear during aluminium electrolysis. The present paper reports on a laboratory study of the wettability of four different carbon materials using the immersion–emersion technique. The effect of polarization of the carbon cathode on the wettability was also included in the study. The measurements demonstrated that the carbon material is poorly wetted by the molten electrolyte or the metal. After polarization of the carbon in the cathodic direction, the cathode became quickly wetted by the molten electrolyte. The presence of aluminium during the experiments resulted in enhanced wettability by the molten electrolyte. The carbon materials were analyzed by microscopy after the experiments and formation of Al4C3 was observed on the surfaces of the materials. The role of sodium in relation to enhanced wettability by molten electrolyte is discussed.
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References
Martinez AM, Paulsen O, Solheim A, Gudbrandsen H, Eick I (2016) Wetting Between Carbon and Cryolitic Melts. Part I: Theory and Equipment, in: Hyland M (Ed.) Light Metals 2015, Springer International Publishing, Cham, pp.665-670.
Thonstad J, Fellner P, Haarberg GM, Hives J, Kvande H, Sterten A (2001) Aluminium Electrolysis: Fundamentals of the Hall-Héroult Process, Aluminium-Verlag Marketing and Kommunikation GmbH, Düsseldorf.
Yuan Y, Lee TR (2013) Contact Angle and Wetting Properties, in: Bracco G, Holst B (Eds.) Surface Science Techniques, Springer, Berlin Heidelberg, pp.3-34.
Martinez AM, Paulsen O, Solheim A, Gudbrandsen H, Eick I (2015) Wetting Between Carbon and Cryolitic Melts. Part I: Theory and Equipment Light Metals pp. 665-670.
Thonstad J, Solheim A, Rolseth S, Skar O (1987) The Dissolution of Alumina in Cryolite Melts Jom-J Min Met Mat S 39 (10), pp. A55-A55.
Solheim A, Gudbrandsen H, Martinez AM, Einarsrud KE, Eick I (2016) Wetting Between Carbon and Cryolitic Melts. Part II: Effect of Bath Properties and Polarisation, in: Hyland M (Ed.) Light Metals 2015, Springer International Publishing, Cham, pp.671-676.
Kvande H, Qiu ZX, Yao KS, Grjotheim K (1989) Penetration of Bath into the Cathode Lining of Alumina Reduction Cells Light Metals, pp. 161–167.
Qiu Z-x, Wei Q-b, Yuo K-t (1983) Studies on Wettability of Carbon Electrodes in Aluminium Electrolysis (I) Aluminium 59 (9), pp. 670–673.
Utigard T, Toguri JM (1987) Radiographic Observation of the Hall-Heroult Electrolysis in Bench Scale Cells, 8. Internationale Leichtmetalltagung Leoben-Wien 1987, Aluminium-Verlag, Leoben-Wien pp.133–137.
Doward RC (1973) Reaction between aluminium and graphite in the presence of cryolite Met Trans B 4 (1), pp. 386-388.
Sørlie M, Øye HA (2010) Cathodes in aluminium electrolysis, Aluminium-Verlag, Düsseldorf.
Johansen JA (2018) Senior Specialist Carbon and Graphite Materials, Elkem Carbon AS Personal Communications, e-mail support.
Ukrainsky Grafit Company (2019) Bottom Blocks. https://ukrgrafit.zp.ua/en/masspod. May, 2019 2019.
(2019) Datasheet for G348 Graphite. https://schunk-tokai.pl/en/g348/. 19 November 2019.
Ratvik AP, Støre A, Solheim A, Foosnaes T (2008) The effect of current density on cathode expansion during start-up Light Metals pp. 973–978.
Wang ZH, Ratvik AP, Grande T, Selbach SM (2015) Diffusion of alkali metals in the first stage graphite intercalation compounds by vdW-DFT calculations Rsc Advances 5 (21), pp. 15985-15992.
Hop JG (2003) Sodium Expansion and Creep of Cathode Carbon, PhD thesis, Norwegian University of Science and Technology, Trondheim.
Mikhalev Y, Øye HA (1996) Absorption of metallic sodium in carbon cathode materials Carbon 34 (1), pp. 37-41.
Thomas P, Billaud D (2002) Electrochemical insertion of sodium into hard carbons Electrochim Acta 47 (20), pp. 3303-3307.
Senanu S, Wang Z, Ratvik AP, Grande T (2020) Carbon Cathode Wear in Aluminium Electrolysis Cells JOM 72 (1), pp. 210-217.
Acknowledgements
Financial support from the Norwegian Research Council and Hydro, Alcoa, Elkem Carbon and Skamol through the project “CaRMa—Reactivity of Carbon and Refractory Materials Used in Metal Production Technology” is acknowledged (Grant No. 236665).
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Senanu, S., Ratvik, A.P., Wang, Z., Grande, T. (2021). Wetting of Carbon Cathodes by Molten Electrolyte and Aluminium. In: Perander, L. (eds) Light Metals 2021. The Minerals, Metals & Materials Series. Springer, Cham. https://doi.org/10.1007/978-3-030-65396-5_92
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DOI: https://doi.org/10.1007/978-3-030-65396-5_92
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