Ketone functionalized task specific ionic liquids for selective tantalum extraction

A novel family of ketone functionalized task specific ionic liquids (TSILs) was designed for the selective extraction of tantalum from sulfuric acid medium. We report the synthesis of functionalized hydrophobic ionic liquids based on piperidium, imidazolium or pyridinium cations bearing ketone moieties and their application in the liquid/liquid extraction of Ta(V). Recovery processes for Ta after extraction were performed and the recyclability of the TSIL was demonstrated. An eco-friendly process based on a TSIL was proposed for the extraction and stripping of tantalum from sulfuric acidic medium. Such system can be used as an alternative to the methyl-iso-butyl ketone (MIBK) which is the most commonly used extractant for the separation and purification of niobium and tantalum by solvent extraction.