To provide a method of refining a high purity indium and a high purity indium alloy, capable of effectively removing impurities contained in indium and an indium alloy at low cost.
In the refining method, the surface of an indium and indium alloy ingot or plate is oxidized beforehand, the indium and indium alloy ingot or plate whose surface is oxidized is melted, after melting, impurities are absorbed, coupled or combined in a slag whose main component is an indium oxide formed on a molten metal of the indium and indium alloy, then the slag is removed so that the indium or the indium alloy is refined. In a method of oxidizing the surface, the surface is heated to 50°C or higher in an oxygen-containing atmosphere and is oxidized, or is oxidized by electrolysis. Among the impurities of the indium, Si is reduced to be 10 wt.ppm or less, Fe is reduced to be 5 wt.ppm or less, Zr is reduced to be 5 wt.ppm or less, and Al is reduced to be 5 wt.ppm or less.
TAKEMOTO KOICHI
KONAKA MITSUYUKI
| JP2004307885A | 2004-11-04 |
Ikki Kogoshi