Carbon-based ionic liquid gels: alternative adsorbents for pharmaceutically active compounds in wastewater

With the aim of obtaining adsorbent systems to be used for the removal of pharmaceutically activecompounds (PhACs) from wastewater, some hybrid ionic liquid gels (HILGs) were obtained from thecombination of ionic liquid-based supramolecular gels and carbon materials, like graphite, graphene andgraphene oxide (graphene OX). The properties of HILGs were investigated by determining their gel–soltransition temperature and rheological features. They were tested for the removal of PhACs belonging todifferent pharmaceutical classes, like antibiotics, antidepressants, anti-inflammatory. In particular, theremoval of carbamazepine (CBZ), diclofenac sodium salt (DCF), ciprofloxacin (CPX) and nalidixic acid (NXA)alone or in combination was performed. Adsorption tests were carried out with the aim of identifying howdifferent operational parameters, like the time of contact, the PhAC concentration, the volume of treatedwastewater and the use under dynamic or static conditions, affect the removal efficiency of the softmaterials investigated. Furthermore, the possibility to recycle and restore the sorbent systems for furtherreuse was also considered. Finally, the most efficient system was also tested in real apparatuses, like a dialysismembrane and columns. HILGs proved to be promising soft materials for addressing the target issue,revealing easy to handle sorbent systems with broad applicability in the field of environmental remediation.