High-Efficiency Flotation Collectors for Magnetite Ores

2019

Peter Zhou, Nouryon; Joseph Zachwieja, Nouryon; Jan-Olof Gustafsson, Nouryon; Henrik Nordberg, Nouryon; Shashi Rao, University of Minnesota-Natural Resources Research Institute

Reverse cationic flotation of silica and silicate gangue materials is widely practiced by the iron ore industry in order to provide high-grade iron feed for the steel industry. Typical cationic collectors used for reverse flotation of silica and silicates are alkyl amines, alkyl amine salts, and more commonly ether monoamines or ether diamines. The two most commercially important iron oxide ores are hematite and magnetite. For flotation of silica from hematite ores, the state of art flotation collectors is based predominantly on ether monoamines, while collectors for magnetite ores are predominantly based on ether diamines. In our current study of the reverse silica flotation of magnetite concentrates, new, highly efficient collectors have been developed resulting in better froth profile than the traditional ether diamines. In one case in particular, it was observed that a new ether monoamine collector surprisingly gave a 20% higher dosage efficiency when compared with the standard ether diamine collector. Methods to improve biodegradability and toxicity of the cationic collectors will also be discussed. Details of the flotation performances of these new, high-efficiency collectors on magnetite concentrates from Europe and Northern Minnesota will be presented, as well as the properties of the resulting flotation froths.

Keywords: Flotation, iron ore, collector, toxicity, magnetite