In connection with the electrolytic production of aluminum the anodic reactions have been studied on carbon microelectrodes by voltammetry and chronoamperometry. Anode gases have been analyzed by gas chromatography on-line during controlled-potential electrolysis in a laboratory-scale aluminum reduction cell. When the voltage exceeds a critical value (about 3 V vs Al/Al3+), the cell current drops precipitously. We attribute this to the formation of a highly resistive film on the surface of the anode. The existence of this putative film was shown to be strictly potential dependent - the film could be formed and removed at will by regulation of applied potential. The rate of PFC generation was found to vary with the magnitude of the anodic overpotential. A PFC reduction strategy that takes into account the design of the power supply is proposed.
|Number of pages||7|
|Journal||Light Metals: Proceedings of Sessions, TMS Annual Meeting (Warrendale, Pennsylvania)|
|Publication status||Published - 2000|
|Event||Light Metals 2000 - Nashville, TN, United States|
Duration: 2000 Mar 12 → 2000 Mar 16