(1. 东北大学 冶金学院，沈阳110819；
2. Department of Chemical and Materials Engineering, University of Auckland, Auckland 1142, New Zealand)
摘 要: 铝电解阳极气泡行为对研究电解质流场模拟和阳极效应都至关重要。本文采用高温透明电解槽观测了底面积为50 cm2 (10 cm×5 cm)的石墨阳极上的气泡行为，实验温度为924 ℃。结果表明：在阳极电流密度为0.3~1.7A/cm2范围内，最大气体覆盖率在48%~65%之间，与工业电解槽炭阳极上的最大气体覆盖率相近，低于文献中小尺寸阳极上观测到的60%~100%。通过SEM/EDS分析发现，气泡成核的优先位置与炭阳极表面的层状结构位置吻合，层状碳结构对CO2气泡润湿性好于致密碳结构，并抑制二氧化碳气泡的滑动，促进大气泡的生成。
关键字: 铝电解；透明电解槽；炭阳极对电解质的润湿性；气泡行为；气泡成核
（1. School of Metallurgy, Northeastern University, Shenyang 110819, China；
2. Department of Chemical and Materials Engineering, University of Auckland, Auckland 1142, New Zealand）
Abstract:In aluminum electrolysis, understanding the anodic bubble behavior has been critical for bath flow field simulation and anode effect investigation. In this paper, bubble behavior on graphite anodes with underside surface area of 50 cm2 (10 cm×5 cm) was studied in a transparent Hall-Heroult electrolytic cell at 924 ℃. The results indicate that the largest bubble coverage on the graphite anodes operated at 0.3-1.7 A/cm2 is in the range of 48%-65%, which agrees with the data obtained on industrial aluminum reduction cell, and lower than that of the smaller anodes, 60%-100%, reported in literatures. Priority sites for bubble nucleation were found to be linked to a highly layered carbon structure on the anode surface combined with SEM/EDS analysis. The layered carbon structure illustrates good wettability to CO2 bubbles, preventing adhered bubbles from gliding across the anode to result in the formation of large bubble.
Key words: aluminum electrolysis; transparent electrolytic cell; wettability of carbon anode to aluminum bath; bubble behavior; bubble nucleation
