Liquid–Liquid Equilibria for 2-Phenylethan-1-ol + Alkane Systems

Abstract

The liquid−liquid equilibrium (LLE) curves for 2-phenylethan-1-ol (2-phenylethanol, 2PhEtOH) + octane, + decane, + dodecane, + tetradecane or + 2,2,4-trimethylpentane have been determined by a method of turbidimetry using a laser scattering technique. Experimental results reveal that the systems are characterized by an upper critical solution temperature (UCST), which increases linearly with the number of C atoms of the n-alkane. In addition, the LLE curves have a rather horizontal top and become skewed to higher mole fractions of the n-alkane, when its size increases. For a given n-alkane, UCST decreases as follows: phenol > phenylmethanol > 2-PhEtOH, indicating that dipolar interactions decrease in the same sequence. This has been ascribed to a weakening in the same order of the proximity effects between the phenyl and OH groups of the aromatic alkanols. DISQUAC interaction parameters for OH/aliphatic and OH/aromatic contacts in the investigated systems are reported. Phenol, or phenylmethanol or 2-PhEtOH, + n-alkane mixtures only differ by the first dispersive Gibbs energy interaction parameter for the (OH/aliphatic) contact. 52 2.1. Materials. Information on source, purity, water 53 contents, determined by the Karl Fischer method, and density 54 (ρ) of the pure chemicals employed along this investigation is 55 t1 collected in Table 1. All the chemicals were used as received. 56 Density values were obtained from a vibrating-tube densimeter 57 and a sound analyzer, Anton Paar model DSA-5000. The 58 repeatability of the ρ measurements is 5 × 10 −3 kg•m −3 , while 59 their relative standard uncertainty is 0.001. Inspection of Table 60 1 shows that there is a good agreement between our density 61 results and those taken from the literature. 62 2.2. Apparatus and Procedure. Mixtures were prepared 63 by mass in small Pyrex tubes of the following dimensions: 0.009 64 m i.d. and about 0.04 m length (free volume of the ampule 65 ≈1.17 × 10 −6 m 3). The tubes were immediately sealed by 66 capping at 0.1 MPa and 298.15 K. Weights were measured 67 using an analytical balance Sartorius NSU125p (weighing 68 accuracy 10 −8 kg). Mole fractions were calculated on the basis 69 of the relative atomic mass Table of 2015 issued by the

Application of CP-PC-SAFT and PC-SAFT for Simultaneous Prediction of LLE and High-Pressure VLE with Universal k12 Values in Systems of Gases and n-Alkanes with N-Methyl-2-pyrrolidone and Some Substituted Aromatic Compounds

“…As a consequence, implementation of the transferable universal k 12 values for different homologue series is substantially hindered. To illustrate this point, Figure S2 of the Supporting Information compares the predictions of UCSTs by CP-PC-SAFT with universal k 12 = 0.023 and PC-SAFT with pure compound parameters thus far proposed for 2-phenylethanol, − acetophenone, aniline, ,, benzaldehyde, − benzylamine, and phenol − with k 12 = 0.017 in their n -alkane homologue series. − The latter value was chosen because it gives the best overall results compared with the other generic k 12 values considered in this study. However, it can be seen that with some sets of pure compound parameters, PC-SAFT still overestimates the UCST data and others underpredict them, while the overall accuracy is substantially worse compared to CP-PC-SAFT.…”

Comparison of CP-PC-SAFT and CS-SAFT-VR-Mie in Predicting Fluid Phase Behavior in Systems of Phenolic Compounds, Aromatic Amines, Acetophenone, and Benzaldehyde

“…Atmospheric pressure LLE in binary systems of alkanes and phenol, 2-methoxyphenol, and 2-phenylethanol. Points–experimental data. − ,,, Solid lines–CP-PC-SAFT with k 12 = 0.023, dotted-dashed lines–CS-SAFT-VR-Mie with k 12 = −0.028.…”

“…The HTHP VLE data on the systems of benzaldehyde are available for the systems with nitrogen, ethane, benzene, and the atmospheric pressure LLE were published for the n -alkane systems. , More significant amount of important data are available for pyridine, including not only the HTHP VLE of its nitrogen, carbon monoxide, and methane systems, along with the atmospheric pressure LLE of the n -alkane systems but also their critical data . Besides that, the atmospheric pressure LLE were measured for the systems of n -alkanes with 2-phenylethanol , o -toluidine and benzylamine . These data are summarized by Table S1 of the Supporting Information.…”

“…The current study expands that approach and compares the predictive capabilities of two models, namely, the simplest CP-PC-SAFT version and the SAFT of Variable Range and Mie Potential parametrized by a Corresponding States approach of Mejía et al , (CS-SAFT-VR-Mie), which also ignores association and polarity. These models are applied for estimating the challenging VLE and LLE data − in 74 binary systems of phenol, m -cresol, 2-methoxyphenol, 2-phenylethanol, 2-ethylphenol, pyridine, aniline, benzylamine, o -toluidine, acetophenone, and benzaldehyde with hydrocarbons, nitrogen, and carbon monoxide, using the universal k 12 values. In the cases of both models, these values were evaluated for the HTHP VLE of the propane(1)–phenol(2) system …”

Predicting the Phase Behavior of Alcohols, Aromatic Alcohols, and Their Mixtures Using the Modified Group-Contribution Perturbed-Chain Statistical Associating Fluid Theory

“…LLE phase diagram of phenol, phenyl methanol, and 2-phenyl-ethanol + n -alkane mixtures and plot of correlated k ij values vs carbon number of n -alkane for PC-SAFT obtained in this work. Symbols are experimental data taken from refs − . Solid lines are mg-SAFT computation results using the 2B dipolar parameter set.…”