以D2EHPA-TOPO为载体的乳化液膜体系萃取磷酸中La（Ⅲ）的工艺及传质机理研究

通过以二（2-乙基己基）磷酸酯／氧化三辛基膦（D2EHPA／TOPO）为流动载体，磺化聚丁二烯（LYF）为表面活性剂，液体石蜡为膜增溶剂，煤油为稀释剂，盐酸为内水相的W／O型乳液，与含La（Ⅲ）的磷酸的外水相进行萃取的过程，制备了W／O／W的双重乳化液膜体系，用单因素法考察了载体浓度，表面活性剂浓度，内相酸度，水乳比等对液膜提取率的影响，确定了最佳工艺条件，迁移率达94．21％以上。并以单浓度递变斜率法研究了载体浓度，表面活性剂浓度，磷酸浓度，H2PO4^-浓度，水相平衡H^＋浓度对分配比的影响，推导出了该乳化液膜的传质机理所经历的步骤。传质机理中包括萃取-反萃表达式，和协萃物组成La（H2PO4）L2（HL）2·（H3PO4）·2TOPO。

Studies on Technology and Transport Mechanism of La3+ from Phosphoric Acid by Emulsion Liquid Membrane Using D2EHPA-TOPO Carrier

The W/O/W double emulsion liquid membrane systems （ELMs） was prepared by the W/O emulsion consisted of D2EHPA/TOPO as carrier, LYF （sulfonated liquid polybutadiene） as surfactant, parafin oil as membrane intensifier, kerosene as diluent, HCl solution as stripping agent, extracted outer aqueous phase La（Ⅲ） in H3PO4 solution in separation process. The influence of the concentrations of carrier, surfactant, HCI solution and volume ratio of feed solution to emulsion on extraction efficiency was investigated by single factor analysis method. The optimum reaction conditions were determined by extraction ratio above 94. 21%. The effect of concentrations of carrier, surfactant, H2PO4^ - , H3PO4, H^＋ of feed solution was studied by single concentration alternation slope method. The transport mechanism which contains extraction and stripping expression was derived and association gathers content La（ H2PO4 ） L2 （ HL）2 · （ H3PO4 ） ·2TOPO was obtained.