化学学报 ›› 2003, Vol. 61 ›› Issue (1): 104-109. 上一篇    下一篇

研究论文

杯芳烃衍生物液-液萃取和液膜传输银的对比研究及机理探讨

陈朗星;张佳;何锡文;曾宪顺;张正之   

  1. 南开大学化学系.天津(300071);南开大学化学系.天津(30071);元素有机化 学研究所.天津(30071)
  • 发布日期:2003-01-15

A Comparison Study between Liquid Extraction and Liquid Membrane Transport of Silver by Calix[4] arene Derivatives

Chen LangXing;Zhangjia;He XiWen;Zeng XianShun;Zhang ZhengZhi   

  1. Department of Chemistry.Tianjin(300071);State Key Laboratory of Elemento-Organic Chemistry,Nankai University.Tianjin(300071)
  • Published:2003-01-15

以4类含硫、硒、氮等杂原子基团二取代的杯[4]芳烃五衍生物(1-14)为中 性载体,在H2O-CHCl3-苦味酸体系萃取银和H2O-CHCl3-H2O液膜体系中传输银进行 了对比研究。萃取和传输结果具有一致性,除了苯并噻唑取代的杯[4]芳烃衍生物 (3-6)外,其它10个含硫、硒、氮的杯[4]芳烃衍生物1-14均对软重金属银和汞 有很高的选择性,而吡啶取代的杯[4]芳烃衍生物7-10对铅有一定的萃取选择性, 其中羟基硫醚取代的杯[4]芳烃衍生物11-14对银的萃取率和传输速率最大。并且 就杯[4]芳烃衍生物对银的传输机理进行了探讨,发现传输速率随源相中金属离子 浓度和有机相中载体浓度的增加而增大,因此推论这是由金属离子浓度梯度推动下 的传输。

关键词: 杂原子, 杯芳烃, 衍生物, 液液萃取, 液膜, 传输,

A study on the extraction properties from aqueous phase to organic phase and the carrier-mediated transport at 25℃ in H2O-CHCL_3-H2O liquid membrane has been performed by using calix[4]arene derivatives (1~14)bearing a wide range of functional groups such as thio (seleno) ether, (benzothiazolyl) thioalkyl, pyridylalkoxy and thioalkyl. The results of liquid-liquid extraction and liquied membrane transport show that the calixarenes have nearly consistent selectivity for silver and mercury ions. All derivatives except calix[4]arenes substituted by (benzothiaxolyl) thioalkyl group (3~6) are efficient extractants and neutral carriers with high selectivity for silver. Calix [4]arenes substituted by pyridylalkoxy group (7~10) show high selectivity for lead in liquid-liquid extraction. The complexation studies reveal that the affinity toward Ag~+,Hg2~+, Pb2~+ is influenced by atom types and lipophilic groups at the lower rim of the caliarenes. The highest extraction and the fastest transport rates of silver are obtained by calix[4] arene substituted by thioalkoxy group (11~14). The transport rates increase with increasing concentration of the cations in the source phase and of the carrier in the CHCl2 phase. There is evidence that the carrier-mediated silver transport through bulk liquid membrane is a concentration gradient diffusion process.

Key words: HETEROATOM, CALIXARENE, DERIVATIVES, LIQUID-LIQUID EXTRACTION, LIQUID MEMBRANE, TRANSMISSION, SILVER

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