Abstract: Fluorine is a harmful impurity in iron ore concentrate that severely affects steel properties and metallurgical
processes. In order to enhance iron recovery and reduce fluoride content in the Bayan Obo magnetic separation iron concentrate
(TFe grade of 57. 40%,F content of 2. 28%),a reverse flotation defluorination test study was conducted. Process mineralogy
indicated that fluoride is primarily present in fluorite and fluorocarbonatite. By optimizing the pH of the pulp,as well as the
types and dosages of collectors and depressants,sodium oleate was selected as the collector and corn starch as the depressant.
Under normal temperature conditions,a closed-circuit process was implemented featuring one roughing,two cleaning,and three
scavenging,with intermediate products sequentially returned. This ultimately yielded an iron concentrate with TFe grade of
64. 76%,recovery rate of 91. 66%,and F content of 0. 178%,with fluoride removal rate of 92. 19%. This research provides a
feasible technical approach for the clean and efficient utilization of high-fluoride iron ore resources,offering valuable reference
for the development of similarly difficult-to-process iron ores.

Key words: fluoride-containing iron concentrate,defluorination by reverse flotation,sodium oleate,corn starch