Effects of superheat and current density on electrolysis expansion performance of semi-graphitic cathode at low temperature

被引：0

作者：

Li, Jie ^{[1
]}

Fang, Zhao ^{[1
]}

Lü, Xiao-Jun ^{[1
]}

Tian, Zhong-Liang ^{[1
]}

Lai, Yan-Qing ^{[1
]}

Xu, Jian ^{[1
]}

机构：

[1] School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China

来源：

Zhongguo Youse Jinshu Xuebao/Chinese Journal of Nonferrous Metals | 2009年 / 19卷 / 12期

关键词：

Cathodes - Sodium - Expansion - Aluminum - Electrolysis - Current density - Temperature;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

The effects of current density and superheat of potassium and sodium penetration in [K3AlF6/ Na3AlF6]-AlF3- Al3O3 on the electrolysis expansion of semi-graphitic cathode melts were studied with a modified laboratory Rapoport apparatus. A mathematical model was introduced to numerically character the electrolysis expansion performance of the semi-graphitic cathode. The results show that potassium and sodium penetrate into the semi-graphitic cathode from exterior to interior. The electrolysis expansion of semi-graphitic cathode increases with increasing current density and superheat. When the superheat increases from 10°C to 50°C, the electrolysis expansion increases gradually from 1.41% to 2.10%. However, as the current density rises, the electrolysis expansion increases obviously before 0.4 A/cm2, and after 0.7 A/cm2 the electrolysis expansion increases obviously again. When the current density ranges in 0.4-0.7 A/cm2, the electrolysis expansion keeps constant relatively, and its increase is the least. In addition, the parameters introduced in the mathematical model can reflect the same information with the curve of electrolysis expansion, and sequentially character the resistance performance to K and Na penetration accurately at low temperature. At low temperature the destructive effect resulted from potassium and sodium penetration can be reduced by reducing superheat and choosing proper current density.

引用

页码：2222 / 2229