(595d) Electrochemically Mediated Regeneration of Ionic Liquids (EMRIL) for Heavy Metal Removal and Water Disinfection

Authors: 
Voskian, S., Massachusetts Institute of Technology
Brown, P., Massachusetts Institute of Technology
Hatton, T. A., Massachusetts Institute of Technology
Rajczykowski, K. P., Silesian University of Technology
The increased use of heavy metals and metalloids in industrial, agricultural and technological applications has led to their wide distribution and persistence in natural water bodies and soil. Elements such as lead, cadmium, nickel, mercury, arsenic and copper may cause multiple organ damage even at low exposure and are therefore of public health significance.

We report the use of novel, task-specific hydrophobic ionic liquids for liquid/liquid extraction of metal ions from an aqueous phase. Selective extraction of 99.95% of solute heavy metals was achieved directly from the aqueous solution of various metal nitrates (Cu, Pb, Ni, Co) at concentrations as low as tens of ppm. The ionic liquid was then regenerated for further extraction via the electroplating of the metal ions onto a steel surface. This allowed for the continuous extraction of such metal ion species from a contaminated stream and the recovery of precious metals via selective electroplating. This concept is of great utility to municipal water treatment as well as metal recovery for the mining industry. Furthermore, these ionic liquids also demonstrate antimicrobial activity, which makes them attractive for in-house water treatment units in the form of immobilized ionogels for both heavy metal removal and water disinfection