Phase equilibria for ternary liquid systems of (water+carboxylic acid or alcohol+1-hexanol) at T=293.15 K: modelling considerations

Liquid-Liquid Equilibria for the System Composed by Water, Acetic Acid, and 1-Hexanol at 293.15 K and Under Atmospheric Pressure Using Refractometry and Densitometry

“…Experimental data for binodal curve and tie-lines together with NRTL model are presented in Figure 1. It is also shown experimental data from Senol (2004). As can be observed in Figure 1, the indirect quantification of the ternary system showed accurate concentration for both aqueous and organic phases, since the filled black points coincided with the binodal curve.…”

“…This paper aimed to compare the phase quantification between indirect methods, i.e., refractometry and densitometry, with a direct method, i.e., gas chromatography (Senol, 2004). For this purpose, binodal curve was determined through the cloud point method and related with the two physical properties investigated in this study.…”

Liquid–liquid equilibria for the system (water+carboxylic acid+chloroform): Thermodynamic modeling

“…The binodal (solubility) curves were determined by the cloud point method in an equilibrium glass cell with a water jacket to maintain isothermal conditions [11][12][13]. The temperature in the cell was kept constant by circulating water from a water bath (Julago Labortechnik GMBH, Germany), which is equipped with a temperature controller capable of maintaining the temperature within ±0.1 K. The major central part of the solubility curves was obtained by titrating heterogeneous mixtures of (water + chloroform) with the acid until the turbidity had disappeared.…”

“…For the water-side and solvent-side limited regions in which the curve and the sides of the triangle are close and exhibit similar slopes, binary mixtures of either (water + acid) or (solvent + acid) were titrated against the third component until the transition from homogeneity to cloudiness was observed. All mixtures were prepared by mass with a Mettler scale accurate to within ±10 −4 g. Mutual solubility values of the (water + chloroform) binary were measured using the method based on the detection of the cloud point [11][12][13]. The transition point between the homogeneous and heterogeneous zones was determined visually.…”

“…As continuation of the previous study [11][12][13], the present work aims to produce new LLE data for the extraction of C2-C5 carboxylic acids from water using a proton-donating chlorinated hydrocarbon compound (chloroform) of high vapor pressure than water and acid. The LLE data have been determined for each of the systems (water + acetic acid, or pyruvic (2-oxopropanoic) acid, or valeric (pentanoic) acid + chloroform) at 293.15 K.…”