Recovery of aluminum from oxide particles in aluminum dross using AlF₃–NaF–BaCl₂ molten salt

Abstract

To recover aluminum from aluminum dross, a floating separation of aluminum alloy from the oxides and subsequent electrolysis of the oxides was carried out in a molten salt bath of 33 mol% AlF₃, 51 mol% NaF and 16 mol% BaCl₂. With A356.0 casting alloy dross, 83% of the aluminum alloy was recovered by the floating separation. A further 4% of metallic aluminum was recovered by electrolysis in the molten salt containing the oxides separated from the dross. The optimum current for continuous operation is discussed considering a balance between the electrowinning and dissolution rates.