The slags containing valuable metals have been generated 2.030 million ton a year, and the amounts of blast furnace slag, covert slag, electro-slag are 1,100 million ton, 600 million ton, and 330 million ton, respectively. The slag is recycled in cement industry or retreated for the recovery of valuable metals to protect the environment and prevent losing of valuable resources.
The purpose of this study is to figure out the behavior of Cu flotation in convert slag with xanthate after selective sulfidizing of copper oxide using sulfidizing reagent. In order to investigate the effect of sulfidization, contact angles were measured and the distribution of the sample components were analyzed with SEM-EDS. Flotation tests were performed to investigate the flotation behavior of metals.
In the result of sulfidizing test, the optimum condition of Cu ion is as follows pulp density 3g/300ml, MIBC 160g/t and SIPX 500g/t. 60min in reaction time. 20℃ in reaction temperature, pH 3.
The concentration of sulfidizing reagent was required double more than that of metal ions to sulfidize metals.
Although the sulfidization of Cu was observed in the result of SEM-EDS, other metals such as Pb also were sulfidized at the same time. This result indicates that the selective sulfidization was not achieved in the tests. After sulfidizing, the contact angle increased from 52ﾟ to 115ﾟ, which shows sulfidizing could produce a hydrophobic surface.
In the result of flotation experiment, the grades of Cu, Zn, Fe, Ni, Pb were 12.41%, 1.49%, 32.19%, 0.11%, 0.66%, respectively, in concentrate and 3.82%, 2.46%, 0.18%, 0.69%, respectively, in tailing. The grade of Cu was higher in concentrate than in tailing. The grade and recovery were 11.0% and 62.8%, respectively, under the following conditions