Abstract: In order to solve the problem of difficult separation of copper and zinc caused by the close floatability of chalcopyrite and sphalerite in a copper-zinc mine in Sichuan，a series of copper flotation condition tests are systematically carried out by using copper preferential flotation process.The self-devel⁃ oped new high selective collector M441 is applied to the flotation of copper minerals in the ore，and the ef⁃ fects of key parameters such as grinding fineness，adjusting agent dosage，collector type and dosage，and foaming agent type on the selective flotation of copper minerals are investigated.The test results show that under the optimized flotation conditions determined by the test，copper concentrate with copper grade of 23.70% and copper recovery of 94.98% can be obtained through a closed-circuit process of one roughing， three cleanings and one scavenging.The new collector M441 has strong selective collecting ability for chal⁃ copyrite，which can significantly inhibit the flotation of sphalerite，so as to achieve efficient separation of copper minerals and zinc minerals in the preferential flotation copper stage. The copper preferential flota⁃ tion process combined with M441 collector provides a feasible technical solution to solve the problems of difficult separation and unstable quality of copper concentrate caused by similar mineral floatability of this kind of copper-zinc ore.

Key words: copper-zinc ore, mineral separation, new collector, preferential flotation