Abstract: Copper smelting slag is the residual slag of copper concentrate after smelting and processing. It is rich in valuable copper and has comprehensive recycling value. Z-200 which is used as copper colloctor in a copper slag concentrator has good selectivity but high price. Therefore， a new cheaper flotation reagent GC-I was developed to replace Z-200. GC-I was synthesized by the reaction of sodium butyl xanthate with dichloroethane. Compared with Z-200， GC-I has lower cost and better selectivity. Under the condition of grinding fineness of - 0.045 mm accounting for 74%， lime consumption of 400 g/t， water glass consumption of 600 g/t and GC-I consumption of 105 g/t， the copper concentrate with copper grade of 23.84% and copper recovery rate of 82.37% was obtained by "one roughing three scavenging" process flow. Under the same condition with Z-200 as collector， the copper grade of the copper concentrate was 21.43%， and the copper recovery rate was 82.23%. According to the closed-circuit test index， the annual cost of new flotation reagent is 699 300 yuan. It is estimated that the cost of flotation reagent will be reduced by 199 800 yuan every year. The economic benefit of new flotation reagent is considerable， which possesses certain application and promotion value.

Key words: Copper slag, Flotation, GC-I collector, Z-200