Highly Efficient and Environmental Process for Removing Alkali Metals from Aluminum Melt

Resumo

A novel process for removing Na and Ca from electrolytic aluminum melt is suggested, where the flux is a mixture of AlF₃ particles with argon. The technology does not employ chlorine, which eliminates the unfavorable consequences of its use, i.e., contamination of the environment and corrosion of the equipment. Aspin rotor is used to provide uniform distribution of AlF₃ and argon in the aluminum melt. The efficiency of removal of alkali metals from the melt at different temperatures, aluminum masses and initial concentrations of Na and Ca is determined. An optimum concentration of the AlF₃ addition in the aluminum melt is suggested.