| 摘要 |
<p>PURPOSE:To recover noble metals such as gold by a pollution-free method at a high yield by treating a recovered material contg. said noble metals with an iodine-contg. anolyte from an electrolytic cell to dissolve and extract the noble metals and subjecting the liquid to alkaline neutralization in a reaction vessel to deposit the noble metals. CONSTITUTION:An electrolyte which consists essentially of KI, contains KIO3 and is adjusted to 13.2pH by KOH is put into the electrolytic cell 4 segmented to a anode chamber 2 and a cathode chamber 3 by a cation exchange membrane 1. An anode and cathode are then electrolyzed. I is formed in the anode chamber and K ions pass the diaphragm and enter the cathode chamber 3 where KOH is formed. The anolyte is sent by a pipe 5 into an extraction cell 6 contg. the recovered material contg. the noble metals such as Au, where the noble metals are dissolved and extracted. The extraction residues are filtered by a filter. The anolyte in which the noble metals are dissolved are sent by a pipe 8 to the reaction vessel 9 and the KOH-contg. catholyte of the electrolytic cell 4 is sent by a pipe 10 to the reaction vessel 9 to deposit the noble metals dissolved in the anolyte. The noble metals are filtered and recovered by a filter 12. The residual liquid is sent into the electrolytic cell 14 and is energized to deposit the residual noble metals on the cathode; thereafter, the noble metals are scraped and are filtered and recovered by a filter 16. Since cyanide, etc., are not used, this method is non-pollutant.</p> |
