The Ion Structure of NiFe₂O₄-10NiO-Based Cermet Anode in the Electrolyte

Abstract:

The problem in the large-scale industrialization for aluminum electrolysis is the corrosion resistance of cermet inert anodes in high temperature molten salts. In this paper, the ion structure of NiFe₂O₄-10NiO-based cermet anode composition in the electrolyte was investigated. The experiment results show that Al-F and Al-O-F complex ion structures are produced at room temperature and perhaps Me-F (Me=Ni, Cu, Fe), Me-O-F or Me-Al-O-F are also formed. Moreover, Al-F and Al-O-F ion structures exist from room temperature to 700 °C and from 1050 °C to 1200 °C; In the rearrangement and melting process of molten salt at 800 °C -1000 °C, the ionic structures are mainly Al-O-F ions; Me-F and Me-O-F ion structures were not found at high temperature, this indicates that Al in Al-O-F complex ion structures is partially replaced by Fe, Ni or Cu to form Me_xAl_aO_yF_z^{(z+2y-2x-3a)-}.

• Periodical: Materials Science Forum (Volume 921)
• Pages: 119-127
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.921.119
• Online since: May 2018
• Authors: Yuan Wang, Han Bing He*
• Keywords: Aluminum Electrolysis, Anode Component, Corrosion, Ion Structure

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