Experimental Study on Sulfuration-flotation of Silver-bearing Copper Oxide Ore by Combined Reagents

The detailed beneficiation experiments were carried out base on process mineralogy, in order to solve the problem of low recovery rate of copper in a silver-bearing copper oxide concentrator from Shanxi Province. The results showed that the grades of copper and silver in the raw ore were 1.24%, 37.2 g/t respectively, and copper mainly existed in the form of malachite and azurite, with silver in the copper oxide minerals. Base on the characteristics of fine distribution size, slow sulfurization speed and easy slime for the copper oxide minerals, the process of sulfurization-flotation-middlings regrinding and separation was conducted, with sodium sulfide + ammonium sulfate as the combined sulfurization reagents, isopentyl xanthate + benzohydroxamic acid as the combined collectors. As a result, a concentration with copper grade of 18.09%, copper recovery of 89.47%, silver grade of 477.56 g/t and silver recovery of 80.60% was obtained. This study provides a guidance for solving the problem of poor separation index of copper and silver in concentrate for concentrator production.