Sustainable and Simple Water-Induced Separation of Ionic Liquid Mixtures

Ionic liquids (ILs) are often considered inseparable once mixed, posing a major challenge for their reuse and recycling. We demonstrate a simple and effective method to separate ILs containing hydrophobic ([NTf₂]^-) and hydrophilic ([OAc]^-) anions under ambient conditions. This process is driven by the thermodynamic behavior of the ILs in presence of water that enables the near-complete (⩾99%) recovery of pure components without complex purification steps. Our findings prove that pure ILs can easily be recovered after being mixed and open new pathways for the sustainable use of ionic fluids in various applications.