Separation and Purification Technology, Vol.174, 29-38, 2017
Contriving to selectively separate drugs with a hydrophilic ionic liquid
The potential of a commercially available imidazolium-based ionic liquid (C(2)C(1)imC(1)SO(4)) to selectively separate two model emerging contaminants, ethynylestradiol and clenbuterol, from aqueous solutions containing non-ionic surfactants (Triton X-100 and Triton X-102) was proved. After a first stage where the binodal curves and tie-lines of the systems were obtained, all the experimental data were suitably correlated with different empirical equations. Then, a 2-step sequential extraction of ethynylestradiol and clenbuterol was investigated by means of a factorial design. In this way, while ethynylestradiol completely partitions to the light layer no matter the operating conditions, clenbuterol extraction can be tuned by a cautious selection of the ionic liquid concentration. Then, while ionic liquid concentrations higher than 70% led to about 4% of clenbuterol extraction in the upper phase, the operation at concentration levels lower than 18% entailed up to 96% of removal. The confirmation of this behavior with synthetic urine proved the relevance of the present data for the implementation of a separation process allowing the selective removal of clenbuterol and ethynylestradiol from aqueous streams, which poses undoubted significant environmental and analytical interest. (C) 2016 Elsevier B.V. All rights reserved.