用配合还原反萃取法从P204有机相中去除Fe(Ⅲ)

Stripping of Fe(Ⅲ) From P204 by Complexation and Reducing

P204萃取剂对Fe^(3+)选择性高,生成的萃合物稳定,但有机相中的Fe^(3+)难以反萃取。研究了采用配合还原反萃取法从P204有机相中反萃取Fe^(3+),考察了几种配合离子及还原剂对Fe^(3+)反萃取的影响。强酸性条件下,Cl-易与Fe^(3+)配位形成FeCl_4^-,硫代硫酸钠对Fe^(3+)的反萃取有明显促进作用,因此,探索了以盐酸为配合剂,硫代硫酸钠为还原剂,通过还原反萃取从P204有机相中去除Fe^(3+)。试验结果表明:在常温、相比Vo/Va=3/1、盐酸浓度5 mol/L、一次振荡时间4 min、硫代硫酸钠加入量为理论量的4倍、二次间歇振荡12min条件下,Fe^(3+)反萃取率达88.6%。该方法可有效去除P204有机相中的Fe^(3+),使有机相得到净化。

P204 can high selectivity extract Fe^3+in solution,so the extraction complex is difficult to be stripped.The stripping Fe^3+from P204 by the process of complexation and reducing was investigated.The effects of several complexation ions and reducing agents on stripping of Fe^3+in the P204 organic phase were examined.Under the conditions of high acid concentration,Cl-complexes Fe^3+to form FeCl-4.The sodium thiosulfate is good reduction agent for stripping the Fe^3+in the P204.The influences of some factors on stripping of Fe^3+from the P204 organic phase were examined.The results show that under the conditions of room temperature,V o/V a of 3/1,hydrochloric acid concentration of 5 mol/L,once oscillation time of 4 minutes,the 4 times theoretical amount of sodium thiosulfate and second intermittent oscillation time of 12 minutes,the stripping rate of Fe^3+can reach 88.6%.Fe^3+can effectively be removed from the P204 by the method.