采用赤铁矿去除高铁闪锌矿浸出液中的铁

Iron-removal by hematite from leaching liquor of high iron sphalerite

研究从高铁闪锌矿溶液中沉淀赤铁矿的过程。考察温度、晶种用量、时间、氧分压对除铁及杂质元素行为的影响。结果表明：除铁率和渣中铁含量随温度、时间、晶种用量的增加而升高，与氧分压关系不大。升高温度和延长反应时间可以提高赤铁矿的纯度。在反应温度190℃、晶种用量20 g/L、反应时间3 h和氧分压0.3 MPa的条件下除铁率达到95%以上，除铁后溶液Fe含量低于2.5 g/L，赤铁矿渣的Fe含量高于50%。K和Ca的入渣率高于95%，Na、F和Ni的入渣率为50%~60%，Zn、Mg、Mn和Cl的入渣率低于1%。

The precipitation process of hematite from the leaching liquor of high iron sphalerite was studied. The effects of temperature, seed addition, time and oxygen partial pressure on the iron precipitation and the behavior of impurities during the process were investigated. The results show that the iron removal rate and iron content of the residue increase with the increase of temperature, time and seed addition, and are independent of oxygen partial pressure. Increasing temperature and prolonging time can improve the purity of hematite. The iron removal rate is larger than 95% at temperature of 190 ℃, seed addition of 20 g/L, time of 3 h and oxygen partial pressure of 0.3 MPa. Iron content of precipitate is larger than 50% and purified solution contains Fe below 2.5 g/L. More than 95% of K and Ca and 50%-60%of Na, F and Ni co-precipitate with hematite, less than 1%of Zn, Mg, Mn and Cl remain in the residue.