Antibiotics in swine husbandry effluents: Laying the foundations for their efficient removal with a biocompatible ionic liquid

The presence of emerging contaminants such as antibiotics is currently urging the search of new techniques to efficiently remove them from the environment. In this work, the exceptional ability of a cholinium-based ionic liquid to salt out aqueous solutions of non-ionic surfactants containing tetracycline and oxytetracycline has been demonstrated. The deep characterization of the phase diagrams has allowed implementing the process with an antibiotic-polluted effluent, reaching extraction levels higher than 96%. The viability of the proposed strategy has been checked in a urine-type effluent and real swine wastewater stream, observing that no important alterations are detected in the phase segregation capacity, and values of antibiotics removal over 70% are reached. The number of cycles that both the ionic liquid and the surfactant can be reused demonstrates the potential of the proposed process to be applied at a real swine wastewater.