| 摘要 |
<p>PURPOSE:To recover Ir by separation from base material in high yield, by mixing the waste articles of insoluble metal electrodes and oxidizing catalysts in which Ir or its oxide is borne on metallic-oxide base material with carbon and then by bringing the resulting mixture into contact with chloride gas. CONSTITUTION:The waste articles of the insoluble metal electrodes and oxidizing catalysts in which Ir or its oxide is borne by the base material of metallic oxides such as TiO2, Al2O3, SiO2, Co2O3, etc., are crushed. Then a mixture 1 of a carbon powder and the above is put into a vessel 4 for converting the metallic oxide into chloride on the bottom of which glass fibers 3 are laid, which is heated in an electric furnace 2 up to a temp. of the dissociation or decomposition temp. of Ir chlorides or above and of the boiling points of the chlorides of base metal or above, that is, 400-1,200 deg.C or above. At the same time, chloride gas such as phosgene, carbon tetrachloride, thionyl chloride, etc., is introduced through a gas-introducing pipe 5. The oxides of base metal are evaporated in the form of metallic chloride, which are liquefied by cooling by means of a cooling pipe 6 and caught in a tank 7. Then the residue in the vessel 4 is subjected to gravity separation, so that metallic Ir can be recovered by separation from the carbon powder and unreacted base material in high yield.</p> |
