Recycling and recovery of ammonium-based ionic liquids after extraction of metal cations from aqueous solutions

The recycling and recovery of ionic liquids (ILs) after the extraction of metal ions were investigated by using trioctylmethyl ammonium camphorate and trioctylmethyl ammonium dodecanedioate, which were synthesized from trioctylamine. The metal ions used in the aqueous solutions were: cadmium, copper and lead with initial concentrations of 50 and 100 ppm. In all the cases, the extraction percentage results were above 90%. After the extraction, the IL recovery was carried out by using solvents with medium polarity indexes. The present work features an extraction mechanism that goes through the use, recycling, recovery and reuse of us applied in the metal extraction process. (C) 2015 Elsevier B.V. All rights reserved.