湿法炼锌赤铁矿法沉铁渣中铁和硫的赋存状态

锌铁分离是湿法炼锌工艺中的关键,赤铁矿法产出的渣性质稳定,对环境友好,有着较大的应用潜力.以硫酸亚铁—硫酸锌溶液体系为对象,研究了反应温度和反应时间对溶液中铁含量和赤铁矿沉淀渣中Fe、S含量及赋存状态的影响.结果表明,在反应温度185℃、氧分压0.4 MPa、转速600 r/min、晶种用量25 g/L条件下,反应时间...

Existing State of Iron and Sulphur in Hematite precipitation from Zinc Hydrometallurgy

Separation of zinc and iron is a key factor in zinc hydrometallurgy.The residue produced by hematite process is stable and friendly to environment,so it has great application potential.The existing state and content of Fe and S in hematite precipitation process was studied in the system of ferrous sulfate and zinc sulfate.The results show that under the conditions of reaction temperature 185℃,oxygen partial pressure 0.4 MPa,rotation speed 600 r/min and seed dosage 25 g/L,the reaction time 3 h,increasing the reaction temperature from 170℃to 200℃may effectively increase the iron content in the residue,reduces the binuclear coordination exchange adsorption between the sulfate radical and the surface of the hematite particles.Meanwhile,the dispersion between the hematite particles is enhanced,and the adsorption of sulfur between the particles is reduced.The S in the liquid after iron removal is in the form of SO₄^2-.The reaction time is prolonged from 1 h to 3 h,the iron removal efficiency increases from 91.23%to 93.63%,and the products are allα-Fe₂O₃.In addition,Fe²⁺ is oxidized faster at the initial stage of reaction,so that part of Fe³⁺ in the solution is in a state of supersaturation,while attached to the spherical seeds at a faster nucleation rate and grow into spindle-shaped small particles.