RECOVERING METHOD FOR NOBLE METAL

摘要

PURPOSE:To allow a noble metal contained in a dilute solution to be adsorbed in high yield and to recover it by passing the dilute solution of the noble metal through an ion exchange resin layer ascendingly from the bottom toward the top. CONSTITUTION:The dilute noble metal-containing solution containing Au in a concentration of 50mg/l is passed through the layer of strong-basic anion exchange resin grains of 0.3-0.5mm diameter ascendingly from the bottom. The slight amount of Au in the solution is adsorbed successively from the bottom of the ion exchange grain layer. The ion exchange resin grains increased in weight by adsorption of Au are allowed to fall one after another, to which new ion exchange resin grains are supplied from the upper part. In this way, the Au-containing solution is continually passed through the layer of ion exchange resin grains low in adsorbed Au content from the bottom toward the top, so that Au can be adsorbed by the ion exchange resin grains in high yield with high adsorptivity. Then the ion exchange resin which has adsorbed Au to the full is incinerated and the incineration residue is dissolved in aque regia, which is reduced to recover Au.