碱焙烧法由氧化锌矿提取ZnO

摘要

引 言锌矿主要分为硫化锌矿和氧化锌矿,目前锌冶炼主要以硫化锌矿为主,随着硫化锌矿的日益枯竭,氧化锌矿的研究和利用显得尤为重要.氧化锌矿是锌的次生矿,是硫化锌矿长期风化的产物,是重要的含锌矿物,其存在形式主要有菱锌矿(ZnCO3)和异极锌矿[Zn4Si2O7(OH)2?H2O],其他还有红锌矿等.氧化锌矿成分复杂,品位低,冶炼困难.目前,氧化锌矿的冶炼工艺主要包括火法和湿法工艺.%Zinc oxide ore was treated by roasting with NaOH. ZnO, SiO2 and PbO reacted with alkali first and then went into solution after digestion. In this paper, orthogonal experiment method was used to optimize conditions for extraction of ZnO from zinc oxide ore by roasting with alkali. The optimized conditions were mass ratio of ore and alkali 1 : 6, holding temperature 400°C , holding time 4 h. Under these conditions, the extraction rate of ZnO was 82. 4%. The main components of zinc extracted slag were stishovite, and Na2ZnSiO4, whose presence impeded further extraction of ZnO. The morphology of slag was irregular, and the particle size was non-uniform.