Abstract:Aiming at non-standard molybdenum concentrate, autothermal reaction was carried out by using heat released from intense oxidation of sulfur in alkali pressure oxidation process. Molybdenum grade in oxidized residue drops to 5% and molybdenum extraction rate is 96.94% after leaching for 2 hours at 160 ℃ under the conditions including ratio of liquid to solid of 7, alkali dosage of 1.2% of mass of molybdenum concentrate, stirring strength of 750 r/min, oxygen filling, and total pressure of 1.6 MPa. Molybdenum concentrate with 15.30% yield, 36.30% molybdenum grade, and 89.18% molybdenum extraction rate is obtained by flotation of autothermal oxidation residues through one roughing, one cleaning and two concentratings. Molybdenum grade in flotation tailings drops to 0.40%. With concentrate added to pressure leaching with proportion of 50%, molybdenum extraction rate is 97.20%. Overall 99.48% of molybdenum is extracted by a combined process of self-thermal pressure leaching and flotation.