Speaker
Description
Understanding of fundamental aspects of metal behavior is a key component of controlling the separation and purification process. This knowledge is based on speciation and oxidation state information leading to numerical thermodynamic parameters [1-3]. Surprisingly, there are still chemical systems with unknown stability constants of metals in the generic mineral acids. However, this situation becomes more complex when a new class of compounds is introduced, so-called non-conventional solvents [4]. This new approach utilizes application of ionic liquids and deep eutectic mixtures. The former is a salt with a melting temperature below 100 °С and they are composed of discrete ions. The latter is a mixture of at least two compounds, resulting in a melting temperature depression in comparison with that of individual moiety, and they consist of hydrogen bond donors and acceptors. These new systems also can be hydrophobic and applicable for metal extraction [5-7]. Recent results on In, Tl, Rh, and Ir behavior in the presence of non-conventional solvents will be discussed.
References
[1] E.E. Tereshatov, M. Semelová, K. Čubová, P. Bartl, M. Němec, J. Štursa, V. Zach, C.M. Folden III, J.P. Omtvedt, J. John, Valence states of cyclotron-produced thallium, New J. Chem. 45 (2021) 3377-3381. https://doi.org/10.1039/d0nj05198e.
[2] E.E. Tereshatov, V. Mazan, M. Boltoeva, C.M. Folden III, Effect of hydrophobic ionic liquids aqueous solubility on metal extraction from hydrochloric acid media: Mathematical modelling and trivalent thallium behavior, Sep. Purif. Technol. 255 (2021) 117650. https://doi.org/10.1016/j.seppur.2020.117650.
[3] M. Volia, E. Tereshatov, M. Boltoeva, C.M. Folden III, Indium and Thallium Extraction into Betainium Bis(trifluoromethylsulfonyl)imide Ionic Liquid from Aqueous Hydrochloric Acid Media, New J. Chem. 44 (2020) 2527-2537. https://doi.org/10.1039/c9nj04879k.
[4] M.F. Volia, E.E. Tereshatov, V. Mazan, C.M. Folden III, M. Boltoeva, Effect of aqueous hydrochloric acid and zwitterionic betaine on the mutual solubility between a protic betainium-based ionic liquid and water, J. Mol. Liq. 276 (2019) 296-306. https://doi.org/10.1016/j.molliq.2018.11.136.
[5] E.E. Tereshatov, M. Boltoeva, V. Mazan, C. Baley, C.M. Folden III, Hydrophobic polymerized ionic liquids for trace metal solid phase extraction: thallium transfer from hydrochloric acid media, New J. Chem. 43 (2019) 8958-8969. https://doi.org/10.1039/c9nj00689c.
[6] J.M. Edgecomb, E.E. Tereshatov, G. Zante, M. Boltoeva, C.M. Folden III, Hydrophobic amine-based binary mixtures of active pharmaceutical and food grade ingredients: characterization and application in indium extraction from aqueous hydrochloric acid media, Green Chem. 22 (2020) 7047-7058. https://doi.org/10.1039/d0gc02452j.
[7] V. Zakusilova, G. Zante, E.E. Tereshatov, C.M. Folden III, M. Boltoeva, Extraction and separation of iridium(IV) and rhodium(III) from hydrochloric acid media by a quaternary ammonium-based hydrophobic eutectic solvent, Sep. Purif. Technol. 278 (2022) 118814. https://doi.org/10.1016/j.seppur.2021.118814.
