The first comparison of the effectiveness of phosphonium ionic liquids in classical solvent extraction and in polymer inclusion membranes for Hg(II) removal

• Published in: Desalination and water treatment 2023-12, Vol.316, p.472-482
• Main Authors: Witt, Katarzyna, Kaczorowska, Małgorzata A., Bożejewicz, Daria, Urbaniak, Włodzimierz
• Format: Article
• Language: English
• Subjects: Cyphos phosphonium ionic liquids; Mercury(II) ions; Poly(lactide); Poly(vinyl chloride); Polymer inclusion membrane
• ISSN: 1944-3986
• DOI: 10.5004/dwt.2023.30163

This paper presents the results of the removal of mercury(II) ions from acidic aqueous solutions. Toxic ions were separated using compounds from the Cyphos group. Six types of ionic liquids were used as extractants in classical solvent extraction, while results showed that Cyphos IL 101 and Cyphos IL 102 presented the highest efficiency for binding mercury(II) ions in given conditions. Therefore, these two compounds were further utilised as ion carriers in studies of transport across polymer inclusion membranes. Membranes were obtained from widely available poly(vinyl chloride) and biodegradable poly(lactide) with the addition of an appropriate plasticizer dedicated to polymer: bis(2-ethylhexyl) adipate or 2-nitrophenyl octyl ether. Moreover, the characterisation of the surfaces of the investigated pure membranes was performed using the Fourier-transform infrared spectroscopy-attenuated total reflectance method and the sessile drop method. Additionally, the membranes, after the processes of mercury(II) ions transport were analysed using Wavelength-dispersive X-ray fluorescence spectroscopy.