Abstract: The effects of modified fatty acid collector DYM-1 on the floatability of single minerals magnesite, dolomite and quartz were investigated, using magnesite single mineral and common gangue minerals dolomite and quartz as research object. Single mineral flotation test results show that at 25 ℃, slurry pH=12.0, DYM-1 dose of 80.0 mg/L, magnesite recovery has reached to 98%, the recovery of dolomite was 73%, the recovery of quartz was 21%, recovery difference value of magnesite with dolomite and quartz is the highest, magnesite and the other 2 kinds of gangue minerals flotation separation effect is best. The spectrum analysis of both DYM-1 and its interaction with single minerals showed that the DYM-1 had hydrogen bond with three single minerals and had chemical adsorption with dolomite surface. The contact angle detection showed that with the dosage increase of DYM-1, the contact angle of magnesite and dolomite increased gradually, and the change rule of the contact angle with the increase of DYM-1 dosage corresponded to the recovery curve.

Key words: Magnesite, Collector, Adsorption mechanism, Flotation