Recovery of Cu-Ce from copper slag by using flotation and chemical methods

In our days, slags are considered secondary resources due to the metals they contain. Copper slags having economical operating grades in terms of Zn, Cu, Ce, Ni, Co, Mo, and V, have complex mineralogy due to their thermal processing based formations. Methods of recovery for copper and other precious metals from slags, have been studied, and for which, flotation plants in industrial scale are operated. In cases where physical or physico-chemical mineral processing methods are not sufficient, hydrometallurgical methods are applied. In this study, the flotation method was applied to a copper slag with 0.9% Cu grade. Copper recovery and the concentration grade were determined to be approximately 40 and 22.7% Cu, respectively. Metal extractions were examined through direct leaching tests. Using H₂SO₄ in the leaching, resulted in gel formation, leading to an investigation of the leach parameters using HCl. Cu and Ce extractions of around 70-80% were attained as a result of a test performed for 2 hours with the addition of 25 g/L H₂O₂ at a rate of 20-25% solids and 300 g/L HCl concentration. An examination of the metal relations, indicated that the dissolution behavior of Cu and Ce was quite similar to the Al dissolution (R²=0.9).