| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method capable of separating and recovering platinum group metals from used insoluble metallic electrodes at high purity by peeling and separating coating layers containing platinum group metal oxides from the metallic electrodes, then removing most of impurities from the coating sludge. SOLUTION: In recovering the platinum group metals from the used insoluble metallic electrodes having the coating layers containing the platinum group metal oxides, the coating layers are physically and/or chemically stripped from electrode base materials. The coating material sludge is heated in a reducing atmosphere to reduce the platinum group metal oxide components to metals and thereafter these metals are chlorinated. The undissolved portions are filtered away in the state of the aqueous hydrochloric acid solution and are then subjected to the separation and removal of the existing cations by an electrodialysis method, by which the high-purity platinum group metals removed of most of the impurities are recovered in the form of chlorides.</p> |
