Abstract: In order to finding an effective way to separate pentlandite and chalcopyrite, the flotation behaviors of pentlandite and chalcopyrite potential adjustment without collector have been investigated.Results demonstrate that pentlandite and chalcopyrite will effective sparated just by frother when the pulp potential controled in the suitable range pulp.When pulp pH is 4.21, the approptate separation potenial range of synchronous flotatation is -550~-750 mV or 250~450 mV, and when pulp pH is 10.27, the approptate pulp potenial range of synchronous flotatation is -200~400 mV.

Key words: Pentlandite, Chalcopyrite, Potential adjustment, Collector-free flotation