ABSTRACT
The general approach to a novel class of functionalized ionic liquids 4-6 bearing grafted diphenylcarbamoylmethylphosphine oxide complexing groups in the cation has been elaborated. The synthetic route comprises the preparation of the intermediate (diphenylphosphorylmethylcarbamoyl)propylimidazole 3, followed by sequential quaternization by alkyl halides (chlorides or bromides) and anionic exchange in the case of ionic liquids bearing the hexafluorophosphate anion. The structures of two ionic liquids were confirmed by X-ray analysis, revealing the strong intramolecular hydrogen bond formed by the acidic protons of the heterocycle and oxygen atom either of the P=O or C=O group, depending on the anion nature. In neutral media, these ionic ligands form complexes ML(2) with europium chloride or europium nitrate via an O,O-bidentate mode similar to known neutral CMPO compounds. The solid phase extractants prepared by immobilization of these FILs on solid matrixes possess sorption activity towards actinides and rare-earth elements in nitric acid solutions.
ABSTRACT
That phosphonium-type ionic liquids (ILs) can be used for preparation of novel solid-phase extractants has been shown. The conditions of IL immobilization on the different matrices (polyacrilonitrile, Amberlite XAD-7, hyper cross-linked polystyrene, and multi-walled carbon nanotubes) were determined. The solid-phase extraction of Pt(IV) from 1-2 M HCl and Pu(IV) from 3 M HNO(3) has been investigated. The possibility of retaining ligands on the solid phases by means of ILs to prepare the complexing solid-phase extractants has been demonstrated.
ABSTRACT
Nowadays much attention is being paid to the determination of trace amounts of noble metals in geological, industrial, biological and environmental samples. The most promising techniques, such as inductively coupled plasma atomic emission spectrometry (ICP-AES), inductively coupled plasma mass spectrometry (ICP-MS) and electrothermal atomic absorption spectrometry (ETAAS) are characterized by high sensitivity. However, the accurate determination of trace noble metals has been limited by numerous interferences generated from the presence of matrix elements. To decrease, or eliminate, these interferences, the sorption preconcentration of noble metals is often used prior to their instrumental detection. A great number of hyphenated methods of noble metal determination using sorption preconcentration have been developed. This review describes the basic types of available sorbents, preconcentration procedures and preparations of the sorbent to the subsequent determination of noble metals. The specific features of instrumental techniques and examples of ETAAS, FAAS, ICP-AES, ICP-MS determinations after the sorption preconcentration of noble metals are considered. The references cited here were selected mostly from the period 1996 - 2006.
