Abstract: The iron grade of magnetic separation concentrate is 65.16% and the contents of sulfur is up to 2.62%. The major iron mineral is magnetite， accounting for 92.23% of total iron. The major sulfur minerals are pyrite and pyrrhotite， which account for 53.72% and 45.67% of the total sulfur， respectively. Sulfur is mainly in the coarse fractions （+100 mesh）and fine fractions （-325 mesh）， and more than 70% sulfur distributed below 200 mesh. In order to reduce the contents of sulfur， the reverse flotation desulphurization experiments are carried out with iron concentrate. The results showed that the sample is treated with closed-circuit process one roughing and one cleaning-scavenging with tailing of cleaning and scavenging， and concentrate of scavenging returning to roughing. In the case of butyl xanthate dosages of 400 g/t in roughing and 100 g/t in cleaning， H106 dosages of 950 g/t in roughing and 450 g/t in cleaning， and terpenic dosages of 50 g/t in roughing and 20 g/t in cleaning， iron concentrate was obtained with iron grade of 66.59%， sulfur grade of 0.29%， iron recovery rate of 91.40% and sulfur concentrate was obtained with sulfur grade of 22.13%， iron grade of 52.75%， sulfur recovery rate of 90.07%

Key words: Magnetic separation iron concentrate, Pyrite, Pyrrhotite, Reverse flotation, Desulphurization