1980 Volume 30 Issue 1 Pages 11-17
Factors governing the recovery efficiency of aluminum in an aluminum chloride bath electrolysis at 160° to 260°C were examined. Dehydrating current loss of electrolyte is 3.03 to 9.09 Ah/kg electrolyte depending on water content in aluminum chloride. Chlorinating loss remarkably increases at the bath temperature above 220°C and reaches to 5.76% at 260°C Filtering loss is not so high as about 0.25% at 180° to 260°C Melting loss depends on temperatures so considerably that the loss is 10.30% at 160°C and is reduced down to 2.75% at 260°C because of improvement in the deposited aluminum shape. Current efficiency of deposited aluminum is almost 98% independently of the bath temperature. The loss of current efficiency about 2% corresponds to the dehydrating loss by moisture of air during electrolysis. Using an anti-chlorinating diaphragm leads to recovery efficiency improved to 94.7% at 260°C.
