Abstract
The effects of KF and LiF addition to the electrolyte on current efficiency were investigated during aluminium electrolysis using base NaF−AlF3−Al2O3−CaF2 system at 980°C in laboratory scale. The electrolysis was performed with a cryolite ratio of 2.5 and with 4% Al2O3 and 5% CaF2. The duration of each electrolysis experiment was 4 h with a graphite anode and a cathodic current density of 0.85 Acm-2. The current efficiency was found to vary with the lithium fluoride and potassium fluoride concentration.