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笔者从合成一开链窝穴体TAEA出发,对冠醚类似物TAEA作为液膜流动载体的选择性迁移性能进行了研究,证明该化合物能在二价铜离子和银离子混合溶液中选择性迁移低浓度(<50ppm)银,提银率达96～99.5％,铜基本上不被提取。该结果比之文献报道的Izatt RM等人以DC18C6冠醚为乳状液膜体系流动载体提取银的提取率85％要高得多。文中介绍了开链窝穴体TAEA的合成路线及其实验操作,并进一步用以TAEA作为乳状液膜的流动载体的液膜体系,进行了铜,银混合液中分离提取贵金属银的实验室研究,优选出提取率高于95％的内外相提取条件,选用硫代硫酸钠溶液作内相制乳状液膜,浓度小于0.025mol/L,液膜可以达到良好的提取分率效果。调节混合溶液初始pH为2左右,仅需离子载体0.2％的TAEA即可将50ppm以下混合铜、银良好分离。提取时间15～20分钟内最好,笔者的研究对TAEA在膜分离技术中的应用前景提供了实验依据。
Starting from the synthesis of an open-chain pocket cavity TAEA, the authors studied the selective migration of the crown ether analogue TAEA as a liquid-membrane flow carrier, demonstrating that the compound selectively migrates in a mixed solution of divalent copper ions and silver ions Low concentration (<50ppm) silver, silver rate of 96 ~ 99.5%, copper is not substantially extracted. This result is much higher than the extraction rate of 85% of silver extracted from the flow carrier of emulsion liquid membrane system by DC18C6 crown ether reported by Izatt RM and others in the literature. In this paper, the synthesis route of TAEA in open-chain pocket cavity and its experimental operation are introduced, and the liquid membrane system using TAEA as the flow carrier of the emulsion liquid membrane is further studied in the laboratory for the separation and extraction of precious metal silver from the mixture of copper and silver , Preferably extraction rate of more than 95% of the internal and external phase extraction conditions, the choice of sodium thiosulfate solution for the internal phase emulsion film, the concentration of less than 0.025mol / L, the liquid film can achieve good extraction fractional effect. Adjust the initial pH of the mixed solution is about 2, only 0.2% TAEA ionophore can be mixed below 50ppm copper, silver good separation. The extraction time is the best in 15-20 minutes, and the author’s research provides the experimental basis for the application prospect of TAEA in membrane separation technology.