锌精矿氧压浸出过程伴生硫铁矿的转化行为

Transformation Behavior of Pyrite in Zinc Concentrate Oxygen Pressure Leaching Process

以硫铁矿为研究对象,研究浸出过程初始硫酸浓度、温度、氧分压、矿物粒度、反应时间对硫铁矿氧压浸出行为的影响。结果表明:硫铁矿氧压浸出过程反应初期为耗酸反应,硫酸的消耗速率大于硫酸的生成速率,反应后期主要是元素硫氧化转化生成硫酸;反应初期浸出液中的铁主要为二价铁离子,反应后期发生铁离子的氧化,且在高温酸性溶液中,三价铁离子可水解沉淀为赤铁矿和铁钒;硫铁矿中的硫元素在氧压浸出过程大部分转化为硫酸并以硫酸根的形式存在溶液中,而少部分以单质硫形式存在于浸出渣中,附着于浸出渣表面,形成包裹层。

Taking pyrite as the research object,the effects of initial sulfuric acid concentration,leaching temperature,oxygen partial pressure,mineral particle size and reaction time on the oxygen pressure leaching behavior of pyrite were studied.The results show that the initial reaction of oxygen pressure leaching of pyrite is acid consuming reaction,and the consumption rate of sulfuric acid is higher than the generation rate of sulfuric acid.In the early stage of the reaction,the iron in the leaching solution is mainly divalent iron ion,and the oxidation of iron ion occurs in the later stage of the reaction,and the trivalent iron ion can be hydrolyzed and precipitated into hematite and iron vanadium in high temperature acidic solution.In the process of oxygen pressure leaching,most sulfur elements in pyrite are converted into sulfuric acid and exist in the leachate in the form of sulfate radical,while a small part exists in the form of elemental sulfur in the leaching residue,which attaches to the surface of the leaching residue and forms a coating.