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研究了N_(1923)作为萃取剂时镧系元素萃取行为的递变规律。在分配比与原子序数之间有明显的四分组效应,萃合物组成不仅与原子数序有关,而且也与萃取酸度有关。轻镧系元素都以配阴离子Ln(SO_4)_4~(5-)形式存在于有机相中,但重镧系元素的被萃阴离子组成与酸度有关,酸度增加配位的硫酸根离子数目减少:Ln(SO_4)_5~(7-)→Ln(SO_4)_4~(5-)→Ln(SO_4)_3~(3-)此外萃合物中有部份伯胺是溶剂化状态存在的,溶剂化倾向随原子序数的增大而增大。重镧系元素>中镧系元素>轻镧系元素溶剂化倾向也随萃取酸度的增加而增大。用红外光谱研究了萃合物中硫酸根的配位状态。对全部镧系元素硫酸根的γ_4都发生了分裂,而对中与轻镧系元素来说,γ_3也发生了分裂,这表明在重镧系的萃合物中。硫酸根是以单齿配体形式存在的,而在中与轻镧系中,至少部份硫酸根是以双齿配体形式配位的。
The change law of lanthanide extraction behavior of N_ (1923) as extractant was studied. In the distribution ratio and the atomic number between the obvious four grouping effect, the composition of the extraction is not only related to the atomic number, but also with the extraction of acidity. The lanthanides are present in the organic phase as anions Ln (SO 4) 4 ~ (5-). However, the composition of the extracted anions of heavy lanthanides is related to the acidity, and the number of coordinated sulfate ions decreases with increasing acidity. Ln (SO_4) _5 ~ (7-) → Ln (SO_4) _4 ~ (5-) → Ln (SO_4) _3 ~ (3-) Some of the extractives have some solvates. The propensity to increase with atomic number increases. Heavy lanthanides> medium lanthanides> light lanthanides The solvation tendencies also increased with increasing extraction acidity. The complexation of sulfate in the complex was studied by infrared spectroscopy. The γ_4 cleavage occurred for all lanthanide sulfate groups, while γ_3 cleavage was also observed for both medium and light lanthanide elements, indicating that it is in the heavy lanthanide complex. Sulfate is present as a monodentate ligand, while in the medium and light lanthanides, at least some of the sulfate is coordinated as a bidentate ligand.