Research on Reaction Mechanism of SiC and AlF₃ in CO Atmosphere

Abstract:

The reaction between SiC and AlF₃ has been investigated in CO atmosphere at high temperature. Experimental results are shown that the reaction intensity between SiC and AlF₃ is accelerated with the rise of temperature. At the temperature of 950 (aluminum electrolytic operation temperature is 935±15), the reaction intensity of SiC and AlF₃ is not high and the major reaction products are SiF₄ gas and Al₄C₃; Al₄C₃ occur severe hydration at room temperature which leads to the pulverization of specimens. The unexpected cells stop should try to be avoided or reduced during the usage of Si₃N₄-bonded SiC sidewall brick in aluminum electrolysis cells because of Al₄C₃ existents possibly.

• Periodical: Advanced Materials Research (Volumes 233-235)
• Pages: 2610-2614
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.233-235.2610
• Online since: May 2011
• Authors: Jia Ping Wang, Yong Li, Xiao Yan Zhu, Jun Bo, Jian Fang Zhang, Hui Li
• Keywords: AlF₃, CO Atmosphere, Reaction Mechanism, Silicon Carbide (SiC)

References

[1] M. Sørlie and H. A. Øye, Cathodes in Aluminium Electrolysis, 2nd edition, Aluminium-Verlag Gmb, HDusseldorf, Germany, 1994.

[2] Zhuxian Qiu, Aluminium Smelting by Pre-baked slot, 3rd edition, Metallurgy Industry Press, Beijing, China, 2005. In Chinese

[3] E.Skybakmoen, H.Gudbrandsen, L. I.Stoen, Chemical resistance of sideline materials based on SiC and carbon in cryolitic melts -A laboratory study. Light metals, p.215~222.1999.

[4] E.Skybakmoen, L.I. Stoen, H.Jannicke, J.H. Kvello, O.Darell, Quality evaluation of nitride bonded silicon carbide sidelining materials. Light metals, p.773~779.2005.

DOI: 10.1007/978-3-319-48200-2_114

[5] Zh.Wang, E.Skybakmoen,T.Grande. Spent Si3N4 Bonded SiC Sidelining Materials in Aluminum Electrolysis Cells. Light metals p.353~358. 2009.

[6] Zh.Wang, E.Skybakmoen, T.Grande. Chemical Degradation of Si3N4 Bonded SiC Sidelining Materials in Aluminum Electrolysis Cells. J.Am.Ceram.Soc.92[6] pp.1296-1302, 2009.

DOI: 10.1111/j.1551-2916.2009.03020.x

[7] E.Skybakmoen, J.H. Kvello, O.Darell, H. Gudbrandsen. Test and Analysis of Nitride Bonded SiC Sideling Materials. Typical Properties Analysed 1997-2007. Light metals, pp.943-948,2008.

[8] E.Skybakmoen. Evaluation of chemical resistance/oxidation of Si3N4-SiC sidelining materials used in Al electrolysis cells. Proceedings of Unified International Technical Conference on Refractories. VolumeIII, pp.1330-1339, Cancun, Mexico, Nov 2001.

[9] Andersen, F. B., Do¨rsam, G., Stam, M., Spreij, M. Wear of Silicon Nitride Bonded SiC Bricks in Aluminium Electrolysis Cells. Light metals. p.413.2004.

[10] Jiaping Wang, Yong Li, Xiaoyan Zhu, Yawei Zhai, Jun Bo, Jianfang Zhang, Research on reaction mechanism of Si3N4 and AlF3 in CO atmosphere. Proceedings of International Conference on Chemical Engineering and Advanced Materials. Accepted. Changsha, China, May28-30, 2011.

[11] Zhaoyou Chen, Chemical Thermodynamics of Refractories, Metallurgy Industry Press, Beijing, China, 2005. In Chinese