| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To selectively separate silver only from a silver-containing nitric acid solution without using chlorine, and to recycle silver. <P>SOLUTION: The method of recovering silver includes a stage where an alkali aqueous solution is added to the silver-containing nitric acid solution to control its pH value to 2 to 7, and neutralization treatment is performed; a stage where granular insoluble tannin is added to the neutralized solution, and mixing is performed; a stage where the temperature of the solution is retained to≥30°C, and the silver contained in the solution is adsorbed on the insoluble tannin; a stage where the insoluble tannin with the silver adsorbed is separated from the solution; and a stage where the insoluble tannin with the silver adsorbed is subjected to burning treatment to recover the silver. <P>COPYRIGHT: (C)2003,JPO</p> |
