Synthesis and application of the magnetic ionic liquid trihexyltetradecylphosphonium tetrachloromanganate for the ultrasound-assisted microextraction of uranium

Abstract

Magnetic ionic liquids (MILs) have received increasing attention as solvent systems in various extraction techniques. The MILs are obtained by incorporating high-spin transition metals within the ionic liquids. In this study, a rapid and straightforward approach based on MILs as the extraction phase was developed to extract and separate uranium from water samples. The hydrophobic MILs trihexyltetradecylphosphonium tetrachloromanganate ([P6,6,6,14+]2[MnCl42−]) was prepared and employed as extraction solvent. The MILs were dispersed into the aqueous sample solution as fine droplets by ultrasonication, and then a rod magnet was used to collect the MIL microdroplets from the aqueous solution. The effect of different experimental parameters such as pH, the complexing agent, the concentration of salt, and sonication time on uranium extraction efficiency were studied and discussed. The practical applicability of the developed method was examined using natural water samples, and the recoveries for the spiked samples were greater than 95 %. The results indicated that the method could be successfully applied to extract and separate uranium from real water samples.

Keywords

• uranium
• microextraction
• magnetic ionic liquids
• ultrasound-assisted extraction