N503为载体的支撑液膜体系中汞(Ⅱ)的迁移研究  

Separation of Hg(Ⅱ) through a Supported Liquid Membrane Using N503 as Carrier

作　　者：吴小宁[1,2] 姚秉华[1] 余晓皎[1] 王骋[1] 

机构地区：[1]西安理工大学应用化学系,陕西西安710048 [2]西安工业大学环境与化工系,陕西西安710032

出　　处：《分析科学学报》2009年第1期55-58,共4页Journal of Analytical Science

基　　金：国家自然科学基金(No.90401009);陕西省自然科学基金(No.SJ08B16)

摘　　要：研究了以多孔聚偏氟乙烯为支撑体，N503为膜载体，煤油为膜溶剂的支撑液膜体系中Hg（Ⅱ）的迁移行为，测定了Hg（Ⅱ）与N503在煤油溶剂中的萃合物组成和条件萃取常数，考察了料液相pH值、载体浓度、料液相及反萃相中Cl浓度等因素对Hg（Ⅱ）迁移的影响，获得Hg（Ⅱ）迁移的最佳条件：料液相pH=2．5～3．0，Cl^-浓度为0．1mol／L，载体浓度为0．706mol／L，反萃相中Cl^-浓度为0．8mol／L。在最佳实验条件下，当Hg（Ⅱ）起始浓度为5．0×10^-5mol／L时，迁移120min，Hg（Ⅱ）的迁移率可达99．6％。Hg（Ⅱ）在N503-煤油支撑液膜体系中的扩散层厚度瓯为1．57×10^-5m，膜内扩散系数d0为7．26×10^-13m^2／s，确立了Hg（Ⅱ）的渗透系数P方程。The transport behavior of Hg（ Ⅱ ） ion through supported liquid membrane was studied with microporous polyvinylidene fluoride film as supported body and N, N＇-di （1-methyl-pentyl） acetamide （N503） as carrier. The stoiehiometry of the extracted species of Hg （Ⅱ） by N503-kerosene was determined. The effects of pH value in feed phase, concentration of carrier in the supported liquid, concentrations of chlorine ion in the feed and strip phase on the transport of Hg（Ⅱ ） were investigated. The optimized conditions for the trasport of Hg（ Ⅱ ） were as follows：the pH value of 2.5-3.0 in feed phase, 0.1 mol/L of chlorine ion in strip phase, 0. 706 mol/L of carrier concentration, and 0.8 mol/L of chlorine ion in strip phase. Under the optimized experimental conditions, the transport rate of Hg（ Ⅱ ） can be reached to be 99.6 % for initial concentration of chlorine ion of 5.0 ×10^-5mol/L and transport time of 120 min. The thickness of aqueous diffusion layer （da） and diffusion coefficient （d0） of Hg（ Ⅱ） through SLM were evaluated by the linear slope method, and they were found to be 1.57×10^-5m and 7.26×10^-13m^2/s, respectively.

关 键 词：液膜 支撑液膜 N503 迁移 汞(Ⅱ) 

分 类 号：O658.2[理学—分析化学]