硫酸铵-溴化四丁基铵水体系液液萃取分离铅  

Separation of Lead with Ammonium Sulfate-Tetrabutylammonium Bromide Aqueous two-phase Liquid-Liquid Extraction System

作　　者：吴艳平[1] 许虹[1] 黄婷婷[1] 

机构地区：[1]佛山科学技术学院理学院,广东佛山528000

出　　处：《河南师范大学学报（自然科学版）》2009年第1期109-112,共4页Journal of Henan Normal University(Natural Science Edition)

基　　金：广东省自然科学基金(7010404)

摘　　要：研究了硫酸铵-溴化四丁基铵(TBAB)-水体系萃取分离铅的行为及其与常见离子的分离条件.试验表明,TBAB的水溶液在硫酸铵的作用下盐析,形成了液-液两相,在pH3～5的克拉克-鲁布斯缓冲溶液中,Pb2+与Br-形成的络阴离子PbBr42-能与溴化四丁基铵TBA+形成疏水性的三元离子缔合物(TBA+)2(PbBr42-)而被萃取到上层TBAB相,其他共存离子:Zn2+,Cu2+,Ni2+,Co2+,Mn2+,Fe3+不被萃取.控制溶液的酸度,该体系能够使Pb2+与常见金属离子Zn2+,Cu2+,Co2+,Ni2+,Mn2+,Fe3+等完全分离.对合成水样进行了萃取分离测定,结果满意.The extraction separation behaviour of lead with （NH4）2 SO4-tetrabutylammonium bromide（TBAB）-H2O system and the conditions for the separation of lead with other metal ions are studied. The results show that TBAB in aqueous solution of ammonium sulfate under salting-out, forming a liquid-liquid two-phase, in a pH 3-5 to Clark-Lubs buffer solution, Pb（ Ⅱ ） can react with Br-to form complex anion PbBr4^2- ,and the resulting PbBr4^2- reacts with TBA^＋ to form ion-association complex （TBA^＋ ）2 （PbBr4^2-）which can be extracted into the upper TBAB phase, other ions： Zn^2＋ , Cu^2＋ , Ni^2＋ , Co^2＋ , Mn^2＋ , Fe^3＋ can not be extraction. Pb（ Ⅱ ） can be totally separated from Zn^2＋ , Cu^2＋ , Co^2＋ , Ni^2＋ , Mn^2＋ and Fe^3＋ by controlling the acidity of the solution. The method has been used for the extraction separation of Pb^2＋ in the synthetic sample of water and the result is satisfactory.

关 键 词：溴化四丁基铵 硫酸铵 液-液萃取 铅 

分 类 号：O658.2[理学—分析化学]