(中南大学 冶金与环境学院，长沙 410083)
摘 要: 采用共沉淀法制备新型的含Al、Ca复合除氟剂。结果表明:在含100 g/L Zn2+、160 g/L H2SO4和450 mg/L F-的硫酸锌电解液中复合除氟剂除氟的最优条件为:pH=3，t=90 min，w=4 g/L，θ=25 ℃。此时，F-浓度可降低至20 mg/L以下，除氟率可达96%，除氟剂吸附容量达108 mg/g。结果表明:仅当Cl-浓度大于800 mg/L时，复合除氟剂的除氟率降至93%。SO42-和Zn2+的浓度对复合除氟剂的除氟效果没有影响，除氟率一直保持在96%左右，除氟过程锌损失率小于5%。吸附平衡曲线结果表明:该型复合除氟剂的吸附过程符合Langmuir 单层吸附模型，最大理论吸附容量143.3 mg/g。
关键字: 锌电积;硫酸锌;除氟;Langmuir 单层吸附模型
（School of Metallurgy and Environment, Central South University, Changsha 410083, China）
Abstract:A novel Al, Ca-containning composite defluoridation agent was synthetized by co-precipitation method. The results show that the optimum conditions to defluoridation from zinc sulfate solution (ρ(F-)=450 mg/L, ρ(H2SO4)=160 g/L, ρ(Zn)=60 g/L) are as follows:pH=3, t=90 min, w=4 g/L, θ=25 ℃. The final ρ(F-) is below 20 mg/L, the fluoride ions removal efficiency is about 96%, and the adsorption capacity is 108 mg/g. The results show that only when the ρ(Cl-) is above 800 mg/L, the fluoride removal efficiency slightly descends to 93%. The ρ(SO42-) and ρ(Zn2+) show no influence on the removal efficiency, zinc loss rate is less than 5% during the defluoridation process. The equilibrium isotherm reasonably fits the Langmuir isotherm model, and the maximum monolayer sorption capacity is 143.3 mg/g.
Key words: zinc electrowinning; zinc sulfate; defluoridation; Langmuir isotherm model
