|About this Abstract
||2020 TMS Annual Meeting & Exhibition
||Aluminum Reduction Technology
||The Influence of Polarization on the Wetting of Graphite in Cryolite-alumina Melts
||Henrik Åsheim, Ingrid Andersen Eidsvaag, Asbjørn Solheim, Henrik Gudbrandsen, Geir Martin Haarberg, Espen Sandnes
|On-Site Speaker (Planned)
The wetting properties of graphite were measured with the immersion/emersion technique in a high temperature lab scale alumina reduction cell. The wetting was measured for untreated, polarized and anode effect polarized samples. Most measurements were made in melts with 1 wt% alumina. Polarisation was found to improve wetting as long as anode effect was not induced, with stronger improvements reached at higher polarisation. Polarisation also decreased the hysteresis between advancing and receding contact angles compared to that of untreated graphite. Anodes polarized to anode effect exhibited consistently very poor wetting for both the advancing and receding direction as well as the smallest wetting hysteresis. The de-wetting process taking place during anode effect was very noticeably only after a few seconds on anode effect, the anode being fully de-wetted from about 60 seconds. Increased alumina content improved bubble detachment presumably from improvement in graphite/electrolyte wettability, notably from 6 wt% alumina.
||Planned: Light Metals