Ionic Liquids in Metal Extraction.
Ionic Liquids in Metal Extraction.
Ionic Liquids in Metal Extraction.
The most commonly used cations and anions in the synthesis of ILs are
Cations - Imidazolium ions, Pyrinidium ion, Ammonium ion, Phosphonium ion.
Anions - [BF4]-, [PF6]-, [RSO4]-, [RSO3]-.
The metal-extractant complexes are more hydrophobic than the metal ions and thus partitioning preferably to the hydrophobic solvent(IL). Example Dicyclohexan-18-crown-6 and other crown ethers can be used to extract alkali, alkaline and few heavy metal ions into ionic liquid. Finally the metal ions can be stripped off the ionic liquid under acidic conditions.
Various other combinations of metal extractant and ionic liquid can be used depending on type of the metal which needs to be extracted out. Task specific imidazolium ionic liquids have been designed such as to serve the purpose of both as extractant and the hydrophobic extracting solvent.
One of the primary driving forces behind research into ionic liquids is the perceived benefit of substituting traditional industrial solvents, most of which are volatile organic compounds (VOCs), with nonvolatile ionic liquids. Replacement of conventional solvents by ionic liquids would prevent the emission of VOCs, a major source of environmental pollution.
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Presented byNitin Singh 09MT3010 Jani Pasha 09MT Amit Dhalia - 09MT