Alkali metals (K and Na) penetration and its effects on expansion of TiB2/C composite cathode during aluminum electrolysis
Affiliation of Author(s):
冶金工程学院
Key Words:
中文关键字:铝电解,碱金属,钾,钠,TiB2/C复合阴极,电解膨胀,英文关键字:aluminum electrolysis,alkali metals,K,Na,TiB2/C co
Abstract:
The behavior of alkali metals (K and Na) penetration in TiB2/C composite cathode and the induced electrolysis expansion
under various conditions in KF melt, NaF melt and their composite melts were investigated. The most important influence factor on
the electrolysis expansion properties of the cathode was revealed, and the elements micro-analysis of cathode profiles was performed.
The results indicate that, under the condition of non-polarization and Al free, no electrolysis expansion occurs. The alkali metal
produced by direct discharge reduction is the most important factor causing the electrolysis expansion, and the maximal expansion is
20.40%. Electrolysis expansion in electrolyte with K is higher than that in electrolyte without K, and the maximal excess magnitude
is 35.13%. Compared with pure potassium salt, composite electrolyte has less destructive effects on the cathode. In addition, no
matter under the condition of polarization or non-polarization, electrolysis expansion in electrolyte with Al is always greater than that
in electrolyte without Al, and the increase amplitude of electrolysis expansion in non-polarization conditions with Al is significantly
greater than that in polarization conditions with Al.