Solubility of ZrO₂ in Cryolite-Based Molten Salt System

Abstract:

Electrolysis of cryolite-based molten salt is an important method for Al-Zr alloy production. The dissolution of ZrO₂ in the melts effects current efficiency and energy consumption of the production process of Al-Zr alloy, so it is most importance to study the solubility of ZrO₂ in the melts. In this paper, the solubility of ZrO₂ in the cryolite-based molten salt of different composition at different temperatures was measured by isothermal saturation method. It was found that ZrO₂ content increased rapidly in the initial stage, but the increase rate was very slow after two hours, so it was thought that ZrO₂ was nearly saturation after two hour-after dissolution. The solubility of ZrO₂ in cryolite-based molten salt increased markedly when increased the temperature and addition of CaF₂. The solubility of ZrO₂ in 2.2NaF·AlF₃-Al₂O₃-CaF₂ molten salt is similar with solubility of ZrO₂ in the 2.2NaF·AlF₃-CaF₂, it is reach 5.5wt%.

• Periodical: Advanced Materials Research (Volume 968)
• Pages: 67-71
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.968.67
• Online since: June 2014
• Authors: Morigen Gaowa Bao*, Zhao Wen Wang, Bing Liang Gao, Zhong Ning Shi, Xian Wei Hu, Jiang Yu Yu
• Keywords: Cryolite-Based Molten Salt, Solubility, Zro₂

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