Visualization of Anode Effect in Aluminum Electrolysis

The aluminum smelting industry is a significant emitter of greenhouse gases. In addition to the emission CO 2 during normal operation, perfluorocarbons (PFCs) are generated when Al O 3 concentration in electrolyte falls below certain critical level, phenomenon referred as anode effect . Understanding mechanism formation has become essential mitigating or preventing its occurrence. Here, occurring at an industrial carbon with underside surface area 50 cm (10 × 5 cm) was observed high-temperature see-through Hall-Héroult electrolytic cell operating 940 °C. visual observation confirmed that caused by intermediate, insulating CF x film. No gas layer large bubbles were effect. sharp increase voltage due insulation continuous intermediate unbroken film, which relatively much higher electrical resistance than and electrolyte.