PURPOSE: To efficiently recover gold of a low content from gold plating washing waste water, etc. by allowing gold to be adsorbed on a high molecular substance having an acid amide bond as at least part of the constitutive unit followed by elution.
CONSTITUTION: A high molecular substance having an acid amide bond as at least part of the constitutive unit, e.g., fibrous substance of nylon is contacted to gold plating washing waste water preferably of pH about 3W5 batchwise or in a column type continuous process to allow gold to be adsorbed. An aqueous KCN soln. of pH about 10 is then contacted to the fibrous nylon with gold throughly adsorbed, whereby the gold is eluted to obtain a high concn. gold soln. The nylon used as the adsorbent can be used repeatedly. It, however, is well profitable to recover gold by incineration after adsorption since this adsorbent is cheap.
KANZAWA CHIYOJI
MASUDA HITOSHI
NAKANE TAKASHI
| US3817745A | 1974-06-18 | |||
| US3565608A | 1971-02-23 |