Liquid–liquid extraction of hydroxytyrosol, tyrosol, and oleuropein using ionic liquids

ABSTRACT

Hydroxytyrosol (HT), tyrosol (TY), and oleuropein (OL) are valuable compounds that can be obtained from olive oil production waste. This study implemented liquid–liquid extraction to obtain HT, TY, and OL from model solutions using two organic solvents, namely, ethyl acetate and n-butyl acetate, and three ionic liquids (ILs), namely, [P_6,6,6,14][Tf₂N], [P_6,6,6,14][DCA], and [omim][Tf₂N]. [P_6,6,6,14][DCA] showed the best performance, with extraction efficiencies of 92%, 96%, and 83% for HT, TY, and OL, respectively. [omim][Tf₂N] showed the highest selectivity in the extraction of TY. Comparisons of the results of a proposed mathematical model with experimental data yielded errors lower than 0.5%.

KEYWORDS:

• Hydroxytyrosol extraction
• tyrosol extraction
• liquid–liquid extraction
• ionic liquids
• mass transfer simulation

Nomenclature

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Acknowledgements

This work was supported by the Chilean National Commission for Scientific & Technological Research through the Project FONDECYT 1161093.

Additional information

Funding

This work was supported by the Comisión Nacional de Investigación Científica y Tecnológica Program of Doctoral Grants for the students Gastón Merlet (year 2013—No. 21130800), Rene Cabezas (year 2013—No. 21130649), and Johan Gonzales (2018—No. 21180578).