一种确定HDEHP聚合态的方法

本文提出了一种测定金属离子在两相中的分配系数以确定HDEHP在不同稀释剂(或萃淋树脂)中的聚合态的方法。此方法较以往根据二聚常数来判断聚合态的方法更为准确可靠,而且可在较低金属离子浓度时测得萃淋树脂萃取容量,也较常用饱和容量法简便。

A METHOD FOR THE DETERMINATION OF POLYMERIC FORMS OF HDEHP

HDEHP with different kinds of diluent may have different polymeric forms, which in the extraction complexes are normally deduced according to their polymeric constants. In this paper, a method is proposed for the determination of the actual polymeric forms of the HDEHP extracting metal-ions. The distribution coefficients of the ions between the organic and aqueous phases (D) are measured as the function of ion concentrations ([Mm+]). Based on these data, the extraction capacity of HDEHP (CHdAn) can be calculated with the following formulations. Ch0nAn=m[Mm+]D/1-(D/D,)1/mBy comparision of the extractive capacity (cH0nAn) with the content or concentration of HDEHP(cH0A), the polymeric form is determined. If cH0An is half of the cH0A, the HDEHP is in dimeric form,and if they are equal to each other, the HDEHP extracting metal ions is in monomeric form.By this proposed method, the extractant is not necessarily saturated with metal ions for measuring extractive capacity.lt is shown that the HDEHP with chloroform or without diluent such as HDEHP-levextrel is in monomeric form and that with kerosine is in dimeric form when extracting Eu3+ in nitric acid.