Phase Equilibrium Investigation on 2-Phenylethanol in Binary and Ternary Systems: Influence of High Pressure on Density and Solid–Liquid Phase Equilibrium

Abstract

Ionic liquids (ILs) are important new solvents proposed for applications in different separation processes. Herein, an idea of possible use of high pressure in a general strategy of production of 2-phenylethanol (PEA) is discussed. In this work, we present the influence of pressure on the density in binary systems of {1-hexyl-1-methylpyrrolidynium bis{(trifluoromethyl)sulfonyl}imide, [HMPYR][NTf], or 1-dodecyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}imide, [DoMIM][NTf] + PEA} in a wide range of temperatures (298.15-348.15 K) and pressures (0.1-40 MPa). The densities at ambient and high pressures are measured to present the physicochemical properties of the ILs used in the process of separation of PEA from aqueous phase. The Tait equation was used for the correlation of density of one-component and two-component systems as a function of mole fraction, temperature, and pressure. The influence of pressure is not significant. These systems exhibit mainly negative molar excess volumes, V. The solid-liquid phase equilibrium (SLE) of [DoMIM][NTf] in PEA at atmospheric pressure was measured and compared to the SLE high-pressure results. Additionally, the ternary liquid-liquid phase equilibrium (LLE) at ambient pressure in the {[DoMIM][NTf] (1) + PEA (2) + water (3)} at temperature T = 308.15 K was investigated. The solubility of water in the [DoMIM][NTf] is quite high in comparison with that measured by us earlier for ILs ( x = 0.403) at T = 308.15 K, which results in not very successful average selectivity of extraction of PEA from the aqueous phase. The [DoMIM][NTf] has shown strong interaction with PEA without the immiscibility region. The ternary system revealed Treybal's type phase equilibrium in which two partially miscible binaries ([DoMIM][NTf] + water) and (PEA + water) exist. From the results of LLE in the ternary system, the selectivity and the solute distribution ratio of separation of water/PEA were calculated and compared to the results obtained for the ILs measured earlier by us. The popular NRTL model was used to correlate the experimental tie-lines in ternary LLE. These results may help in a new technological project of "in situ" extraction of PEA from aqueous phase during the biosynthesis.

The Density, Speed of Sound, Viscosity, and Thermal Conductivity of 1-Dodecyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide and Its Ionanofluid with Graphene

“…Figure shows the deviations of all of these published data from our data, including their expanded uncertainties at the 95% confidence level. It is clear that these existing density data do not agree with our data within their claimed mutual uncertainty, except for those of Domańska et al , and Lamas et al (up to 330 K). This is possibly due to impurities in the ionic liquid and/or the reported water content.…”

“…Several authors have published results for the density of this ionic liquid as a function of temperature, all of which were determined by using the vibrating tube method (which was what was used in this study as well). Thus, we are able to compare our present data with those of Tariq et al, Tariq et al, Domańska and Wlazło, Lamas et al, Hazrati et al, Domańska et al, and Song et al, as shown in Figure .…”

“…The ionic liquid 1-dodecyl-3-methyl­imidazolium bis(trifluoro­methyl­sulfonyl)imide (CAS no. 404001-48-5), termed [C 12 mim][(CF 3 SO 2 ) 2 N], has been studied for several applications, such as gas solubility, phase equilibrium studies, , the separation of butan-1-ol/water, and thermal energy storage, and studies on its thermophysical properties , and nanostructure have been performed. Lamas et al and Zhang and Reddy have suggested that, by increasing the length of the carbon chain of this ionic liquid, its heat capacity and thermal conductivity increase.…”

Experimental Data of Fluid Phase Equilibria- Correlation and Prediction Models: A Review

“…That is why a vast amount of experimental work has dealt with measurements of the SLE/LLE/VLE phase diagrams in ILs-based systems. The phase equilibria in systems that contain ILs has been the object of investigation in our group from many years [33][34][35][36][37][38][39][40][41][42][43][44][45].…”

“…The SLE or LLE data provide a good tool for studying the thermodynamic behavior of many systems. Thus, many phase equilibria of infragrance materials have been measured by our group, for example, such as 2-phenylethanol, PEA (roses oil) [32][33][34][35]41,42].…”