REMOVAL OF SMALL AMOUNT OF ALKALI METAL OR ALKALINE EARTH METAL IN MOLTEN ALUMINUM OR ALUMINUM ALLOY

摘要

Small quantities of alkali metal and alkaline earth metal impurities are removed from an aluminum melt by introducing a source of sulfur such as elemental sulfur, which combines with the impurity to form an impurity-containing slag, purging the melt with gas to remove excess sulfur, and separating the purified melt from the slag.