Poster (EARTH)

[PE1-017] The solubility of palladium in the FeO_x-SiO₂ slags at 1573K

○Ryo Ogasawara², Hidehiro Sekimoto², Katsunori Yamaguchi¹ (1. Waseda University, 2. Iwate University)

Keywords:platinum group metals, slag loss , activity coefficient , Cu-Pd alloy

There is an increasing trend in the copper smelters to recycle electronic materials, which contain relatively high concentration of platinum group metals. Platinum group metals lost in the slag is increasing with increasing of treated scrap amount. To determine the portion of the platinum group metals chemically dissolved in the slag will be a key factor to improve the recovery of those metals.
An experimental study was carried out to determine the solubility of palladium in the FeOx-SiO₂ slag equilibrated with a pure palladium and the liquid Cu-Pd alloy at 1573 K and the range of oxygen partial pressure from 10^-9 to 10^-7. The solubility of palladium in the slag tends to increase with increasing oxygen partial pressure and content of copper in the slag. Based on the measured palladium solubility, activity coefficients of palladium oxide in the FeO_x-SiO₂ slag were derived. The activity coefficients decrease with increasing copper contents in the slag. Therefore, lower copper content in the slag tend to lower precious metals dissolution in the slag.