Solvent extraction of heavy metals with macrocyclic ligands based on calix[4]arenes
Solvent extraction of heavy metals with macrocyclic ligands based on calix[4]arenes
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基于杯[4]芳烃的大环配体溶剂萃取重金属
DOI：
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发表时间：
1999
期刊：
影响因子：
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通讯作者：
R. Ludwig
中科院分区：
文献类型：
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作者：
N. K. Dung;R. Ludwig
配体1是一种含冠-6结构的杯[4]芳烃类化合物，能有效地从弱酸性溶液中萃取重金属离子Hg2+和Pb2+，因为它们的离子半径相容。通过与相应的酯类化合物2的比较可以看出，CO2H基团是金属萃取所必需的。配体3作为冠醚-5也能够从弱酸性溶液中萃取较小的阳离子，如锌和镉。含四个CO2H基团的化合物5对Hg2+和Pb2+的定量萃取分别在pH>2.5和2.8时进行。即使水相中存在水溶性有机络合剂，如EDTA，也会在一定程度上发生萃取。用0.75M硝酸进行定量反萃取。
Ligand 1, a calix[4]arene-based compound with a crown-6 moiety, efficiently extracts the heavy metal ions Hg2+ and Pb2+ from weakly acidic solutions due to their compatible ion radius. The CO2H groups are essential for the metal extraction, as seen from a comparison with the corresponding ester compound 2. Ligand 3 as a crown-5 is also capable of extracting smaller cations such as Zn2+ and Cd2+ from weakly acidic solutions. Compound 5, bearing four CO2H groups, shows quantitative extraction for Hg2+ and Pb2+ at pH values above 2.5 and 2.8, respectively. Extraction takes place to some extent even if water-soluble organic complexing reagents are present in the aqueous phase, such as EDTA. Quantitative back-extraction is achieved by using 0.75 M HNO3.