Designing eutectic mixtures for the extraction of 2-phenylethanol (PEA) from aqueous phase

Abstract

The field of industrial biotechnology is rapidly growing. This includes the use of biosynthesis of the fragrance-row materials in chemical industry, food industry, cosmetical and pharmaceutical industry. The production of 2-phenylethanol (PEA), which is an important flavor and fragrance compound, with a rose-like odor has been significantly increased last decade. The ionic liquids (ILs) and binary eutectic mixtures (EM) are proposed as an entrainers for the extraction of PEA in a biphasic biosynthesis. ILs and DES reveal many unique properties which make them very interesting for applications in modern ‘green’ technologies. In this work we present new experimental results on (solid, or liquid + liquid) phase equilibrium (SLE/LLE) measurements of twelve binary systems composed of pyrrolidinium-based ILs (namely: 1-butyl-1-methylpyrrolidinium chloride, [BMPYR][Cl] and 1-butyl-1-methylpyrrolidinium bis{(trifluoromethyl)sulfonyl}imide [BMPYR][NTf2] as well as 1-hexyl-1-methylpyrrolidinium chloride, [HMPYR][Cl] and 1-hexyl-1-methylpyrrolidinium bis{(trifluoromethyl)sulfonyl}imide [HMPYR][NTf2] with alcohols (1-decanol, 2-methyl-1-butanol, 2-methyl-2-butanol) and oleic acid. Additionally, three ternary LLE mixtures are presented {IL, or EM + PEA + water} at T = 308.15 K and ambient pressure. The data reveals that [HMPYR][NTf2] ionic liquid is more attractive than [BMPYR][NTf2] and that EMs ([BMPYR][NTf2] + 2-methyl-2-butanol) and ([HMPYR][NTf2] + 2-methyl-2-butanol) present worst selectivities and solute distribution ratios than those observed for pure ILs. However, they may be assumed as an alternative, less cost solvents for the separation of PEA from the water phase using liquid-liquid extraction at ambient conditions.