P507盐酸体系萃取分离铈和镨.docVIP

 P507 盐酸体系萃取分离铈和镨 摘要：为了获得高纯单一的稀土元素，本文利用萃取法从盐酸体系中分离铈 Ce3+和镨 Pr3+。 以 P507 为萃取剂，煤油为稀释剂，正辛醇为添加剂，对 CeCl3 和 PrCl3 进行萃取实验研究， 考察了料液浓度和酸度、P507 浓度和皂化率对稀土金属分离的影响。结果表明，Ce3+和 Pr3+ 的萃取率随 P507 浓度的增大而增大，随 P507 皂化率提高而先增大后减小，皂化率应该保 持在 50%以内，以防乳化现象；在 pH 为 3~4 时，原料液质量浓度 0.5 g/L，皂化率 40%时， 0.05mol/L P507 对 Ce3+和 Pr3+萃取率均达到 99%以上，分离因子可以达到 2.28；2mol/L HCl 对 CeCl3 和 PrCl3 进行反萃，反萃率均可以达到 100%。 关键词：稀土金属；萃取；皂化；反萃 中图分类号：TF845.6 Solvent extraction separation of cerium and praseodymium from hydrochloric solution with P507 Xia Jie1, Ren Zhongqi1, Wang Yundong2 (1. Membrane Separation Process and Technology Key Laboratory of Beijing, Beijing University of Chemical Technology, Beijing 100029, China; 2. State Key Laboratory of Chemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China) Abstract: Rare earths, provided with special physical and chemical properties, are generally used in metallurgy, petrochemical industry, various functional materials and glass ceramics. Ce3+ and Pr3+ have been separated from HCl solution by extraction to obtain single rare earth using P507 as extraction agent, kerosene as diluent, and octyl alcohol as additive. The effect of concentration and saponification ratio of P507, the pH and metal concentration of feed liquid on the separation of Ce3+ and Pr3+ were studied. The results show that the saponificated P507 has a good extraction performance for Ce3+ and Pr3+. As saponification ratio increases, the extraction efficiency of Ce3+ and Pr3+ increases and then decreases. The saponification ratio should not be higher than 50% to avoid emulsification. When the pH of feed liquid keeps between 3 and 4, the mass concentration of feed liquid is 0.5 g/L, saponification ratio is 40%, the extraction efficiency of Ce3+ and Pr3+ can achieve more than 99% and separation factor 2.28. As for stripping, both Ce3+ and Pr3+ can be totally stripped from organic phase by 2 mol/L HCl. Key words: rare earths; extraction; saponification; stripping 0