共生氧化物对锌硅酸盐矿物氨浸行为的影响研究

为探讨高碱性脉石型低品位氧化-硫化混合锌矿氨浸行为的影响因素,采用水热氨浸法研究了混合矿中异极矿氨浸的较佳工艺条件,并研究了低品位矿石中共生的氧化物(MgO、CaO、SiO_2、MnO_2)对异极矿浸出行为的影响。研究结果表明:异极矿水热氨浸较佳条件为:搅拌速度400 r/min,浸出时间30 min,总氨浓度5 mol/L,氨∶氯化铵摩尔比1∶1,浸出温度60℃,液固比20∶1,此时锌浸出率为81.9%。共生氧化物MgO、CaO、SiO_2均对异极矿的浸出有抑制作用,其中,CaO使得锌的浸出率呈规律性减小,MnO_2抑制作用不明显。

Effects of Associated Oxides on Ammonia Leaching of Refractory Zinc Silicate Ore

In order to discuss the influencing factors for ammonia leaching of the combination of oxidized?sulfide zinc ore with low grade and high content of alkaline gangues, hydrothermal ammonia?leaching process was adopted in the experiment to investigate the optimal conditions for ammonium leaching of hemimorphite, as well as effects of associated oxides ( MgO, CaO, SiO2 , MnO2 ) in the low?grade ores on the leaching rate of hemimorphite. Results indicated that zinc leaching rate reached 81.9% under the optimal conditions, including agitation rate at 400 r/min, reaction time of 30 min, the total concentration of NH3 and NH4 Cl at 5 mol/L, molar ratio of NH3 to NH4 Cl at 1∶1, liquid/solid ratio at 20∶1, leaching temperature at 60 ℃. It is also shown that the associated oxides ( MgO, CaO, SiO2 ) all brought inhibiting effects on hemimorphite leaching behavior and zinc leaching rate decreased regularly along with the increasing of CaO, however, MnO2 brought little inhibiting effect.