环烷酸-酸性磷酸酯-庚烷体系萃取有机相的红外光谱研究

将环烷酸(NA)与2-乙基己基磷酸单2-乙基己基酯(PC88A)混合，以浓KOH溶液皂化，研究了高皂化度(80％)油包水型微乳萃取钕过程的有机相的结构变化。通过红外光谱分析，发现萃取钕过程随着负载率增加，COOH伸缩振动吸收峰 、COO-的反对称峰及PO伸缩振动吸收峰的峰位均向低波数移动。结果表明：皂化NA和PC88A的混合体系萃钕过程，NA与PC88A存在相互作用;它们都与Nd3+作用，但PC88A作用较环烷酸完全，萃取有机相中，P—O—H伸缩振动吸收峰消失，还残留部分COOH没有完全转化为COO-;环烷酸、PC88A与钕之间形成的萃合物具有复杂结构。

FTIR Investigation of Organic Phase Containing Rare Earth Ion in Naphthenic Acid-Phosphonate Ester-Heptane System

Naphthenic acid (NA) was mixed with PC88A in heptane, and 10 moL x L(-1) KOH aqueous solution was used to saponify the solution subsequently. The transparent and clear appearance of the obtained solution indicated the formation of w/o micell and microemusion. In the present study, micell with high saponification percentage (80%) was used to extract neodymium. The organic phase structure was characterized using FTIR spectroscopy in the extraction process. IR spectra indicate that the characteristic peaks of nu(COOH), nu(s)(COO-) and nu(P=O) shift to lower wavenumbers as the loading of Nd in organic phase increases. The results demonstrated that Nd(III) are coordinated to P=O and COO- groups simultaneously, and the supramolecules with self-assembly structure was formed containing PC88A and NA, which were binding with Nd(III) in the extracted organic phase.