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论述了用Ｃｘａｎｅｘ２７２、３０２和３０１溶剂萃取铜（Ⅱ）的机理。从硫酸介质中萃取铜强烈地依赖于膦酸中硫的取代，而铜被Ｃｙａｎｅｘ３０２和Ｃｙａｎｅｘ３０１全部萃取发生在ｐＨ０以下。在这些条件下不可能用常规的斜率分析，因而络合物的理想配比与几何形状是通过对被络会离子的电子光谱、磷－３１核磁共振光谱（３１Ｐ－ＮＭＲ）和快原子轰击质谱（ＦＡＢ－ＭＳ）的分析推导出来的。萃取时．Ｃｕ（Ⅱ）被含硫配位基还原成Ｃｕ（Ⅰ），同时萃取剂被氧化。业已表明，铜与这些配位基以１∶１的理想配比化合而形成多核齐聚络合物；在多核齐聚络合物中，配位基架桥于金属中心之间。铜与含硫配位基所形成的络合物稳定性的提高可用硬－软酸－碱概念和金属中心ｄ轨道与给予体原子之间的π键来解释。
The mechanism of copper (Ⅱ) extraction with Cxanex 272, 302 and 301 was discussed. Extraction of copper from sulfuric acid medium strongly relies on the replacement of sulfur in the phosphonic acid, whereas extraction of copper by all of Cyanex 302 and Cyanex 301 takes place below pH 0. Under these conditions, it is not possible to use conventional slope analysis, so the ideal ratio and geometry of the complexes are determined by electron spectroscopy, P-31 NMR spectroscopy and fast atom bombardment mass spectrometry (FAB-MS) analysis derived. When extracted. Cu (Ⅱ) is reduced to Cu (Ⅰ) by sulfur-containing ligands and the extractant is oxidized. Copper has been shown to complex with these ligands at a 1: 1 stoichiometry to form multi-core oligomeric complexes; in multi-nuclear oligomeric complexes, the ligand bridges between metal centers. The increase in the stability of the complex formed between the copper and the sulfur-containing ligand can be explained by the hard-acid-base concept and the π bond between the d center of the metal center and the donor atom.