METHOD FOR TREATING MOLTEN ALUMINUM FOR DECREASING Ti, V AND B

摘要

PROBLEM TO BE SOLVED: To provide a treating method by which not only the amounts of Ti and V but also the secondarily increasing amount of B can be decreased and high-purity aluminum usable for electrolytic capacitors and magnetic discs can be obtained. SOLUTION: Molten aluminum or molten aluminum alloy each containing Ti and/or V as impurity is held at 700-900 deg.C. Then B in an amount larger by 10-200 mass ppm than the total chemical equivalent calculated as TiB2 and/or VB2 is added to the molten aluminum or molten aluminum alloy to remove Ti and/or V in the form of a Ti-B compound and/or a V-B compound. Further, a carbon-containing material is added to the melt to separate unreacted B contained in excess from the molten aluminum or molten aluminum alloy. It is effective to blow gaseous CO2, liquefied petroleum gas, etc., as the carbon- containing material.