| abstract |
PROBLEM TO BE SOLVED: To provide an advanced method and apparatus for refining metals such as indium containing various impurity elements, which were difficult to purify with conventional techniques. SOLUTION: A raw material indium having a purity of 99.99% is put in a raw material crucible 8 and a degree of vacuum of 1 × 10 −4 Torr (1.3). When heated to 1250 ° C. by the upper carbon heater 6 in a vacuum atmosphere of (× 10 −2 Pa), indium evaporates and condenses on the inner surface of the inner cylinder 3, and is dropped and collected in the liquid storage section 9 below the cylinder 11. The impurity element having a lower vapor pressure than indium remains in the raw material crucible 8 and is separated. Next, the recovered indium in the liquid storage unit 9 is heated to 1100 ° C. by the lower carbon heater 7, and among the generated steam, the vapor of the impurity element having a higher vapor pressure than indium is removed from the cylindrical body 1. 1, the indium vapor passes through the graphite diffusion plate 12 in the upper part inside and is discharged out of the system. On the other hand, the indium vapor comes into contact with the diffusion plate 12 and is re-condensed and returns to the liquid storage section 9. 0.999% of highly purified indium can be obtained. |