铁闪锌矿加压浸出动力学

以人工合成的高纯度铁闪锌矿为对象，研究了其加压浸出动力学. 在初始硫酸浓度为0.77 mol/L、液固比100 mL:10 g、搅拌转速550 r/min条件下，在0.1~0.5 MPa和388~418 K范围内考察了氧分压和浸出温度对锌、铁浸出速率的影响. 结果表明，388 K时浸出60 min，随氧分压由0.1 MPa升高至0.5 MPa，锌浸出率由35.69%增大至89.80%；氧分压为0.3 MPa时浸出30 min，随浸出温度由398 K升高至418 K，锌浸出率由44.00%增大至85.93%. 此外，在锌浸出达到平衡及铁明显水解沉淀前，锌、铁浸出率与浸出时间呈直线关系，锌、铁浸出速率随氧分压和浸出温度升高而增大，锌的浸出速率始终高于铁. 铁闪锌矿氧压酸浸反应的表观活化能为44.0 kJ/mol，锌浸出遵循界面化学反应控制的未反应核收缩模型. 经研究证实，人工合成矿的浸出实验结果与实际精矿的浸出实验结果一致.

Pressure Leaching Kinetics of Marmatite

The pressure leaching kinetics of synthesized marmatite was studied. The effects of oxygen partial pressure in the range of 0.1~0.5 MPa and leaching temperature in the range of 388~418 K on leaching rates of zinc and iron were respectively investigated in the following conditions: initial concentration of H2SO4 as 0.77 mol/L, ratio of liquid to solid as 100 mL:10 g, and agitation speed as 550 r/min. The experimental results show that the leaching rate of zinc in 60 min at 388 K is increased from 35.69% to 89.80% when the oxygen partial pressure is raised from 0.1 to 0.5 MPa. The leaching rate of zinc in 30 min with the oxygen partial pressure of 0.3 MPa is increased from 44.00% to 85.93% when the leaching temperature is raised from 398 to 418 K. The experimental results also show that the linear relationship between the leaching rate of zinc and leaching time exits before the leaching equilibrium of zinc is achieved. The linear relationship between the leaching rate of iron and leaching time exits before iron is significantly precipitated by hydrolysis. The leaching rate constants of zinc and iron all increase with the increase of oxygen partial pressure and leaching temperature. The leaching rate constant of zinc is always higher than that of iron. The apparent activation energy is determined as 44.0 kJ/mol for the pressure leaching of marmatite. The leaching of zinc follows the shrinking core model with surface reaction control. The experimental result of the synthesized ore coincides with that of marmatite concentrate.