Determination of the Critical Micelle Concentration of Imidazolium Ionic Liquids in Aqueous Hydrogen Peroxide

Bastian Zehner; Fabian Schmidt; Wolfgang Korth; Mirza Cokoja; Andreas Jess

doi:10.1021/acs.langmuir.9b02759

Determination of the Critical Micelle Concentration of Imidazolium Ionic Liquids in Aqueous Hydrogen Peroxide

Langmuir. 2019 Dec 10;35(49):16297-16303. doi: 10.1021/acs.langmuir.9b02759. Epub 2019 Nov 27.

Authors

Bastian Zehner¹, Fabian Schmidt², Wolfgang Korth¹, Mirza Cokoja², Andreas Jess¹

Affiliations

¹ Chair of Chemical Engineering , University of Bayreuth , Universitätsstraße 30 , D-95440 Bayreuth , Germany.
² Chair of Inorganic and Metal-Organic Chemistry, Faculty of Chemistry and Catalysis Research Center , Technical University of Munich , Lichtenbergstraße 4 , D-85747 , Garching bei München , Germany.

PMID: 31722181
DOI: 10.1021/acs.langmuir.9b02759

Abstract

The critical micelle concentrations (CMCs) of several imidazolium-based ionic liquids (ILs) in aqueous H₂O₂ (50 wt % in H₂O) were determined by tensiometry, conductometry, and the rate of catalytic epoxidation of cis-cyclooctene. CMC values in aqueous H₂O₂ were significantly lower compared to values in pure water. In both H₂O₂ solution and water, the CMC of all ILs decreases with an increasing alkyl chain length and increases with a rising temperature. The degree of micelle ionization of 1-methyl-3-octylimidazolium tetrafluoroborate ([OMIM][BF₄]) was calculated by conductometry in a temperature range of 22-70 °C.