Liquid–liquid equilibria for the ternary system water + octane + 2-butyloxy-ethanol
Introduction
Mixtures of the type water + oil + surfactant are widely applied in many industrial processes and applications, e.g., pharmaceuticals, liquid–liquid extraction, herbicides, tertiary oil recovery and in the fundamental research of wetting transitions and critical phenomena [1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11]. The homologous series of nonionic surfactant polyoxyethylene alcohol CH3(CH2)i−1(OCH2CH2)jOH, abbreviated by CiEj hereafter, are extensively used as detergents and emulsifying agents and also applied both in industrial and in fundamental research [7], [8], [9], [10], [11], [12], [13].
Kilpatrick et al. [14] have studied the phase behavior of water + CnH2n+2 (n = 6, 8, 10, 12, 14) + C4E1 at 298.15 and 303.15 K. Precise liquid–liquid equilibrium measurement data of water + decane + C4E1 mixture has been investigated by Brandani et al. [15] On the other hand, Lin and Chen [16], [17] have reported the phase diagrams of water + dodecane + C4E1 and of water + tetradecane + C4E1 system at temperatures ranging from 298.15 to 338.15 K. Su et al. [18], [19], [20], [21], [22], [23] replaced the ethylene glycol ethers with propylene glycol ethers (CH3(CH2)i−1(OCH2CHCH3)jOH, abbreviated by CiPj), and performed a series of liquid–liquid equilibrium measurements for the water + CnH2n+2 (n = 12, 14, 16) + C3Pj (j = 1, 2) system at three different temperatures.
In this study, liquid–liquid equilibrium data were measured for the ternary system water + octane + 2-butyloxy-ethanol (C4E1) in the temperature range from 283.15 to 303.15 K under atmospheric pressure by gas chromatography. The fish-shaped phase diagram of the system was also performed to search for the lower/upper critical solution temperatures. These experimental liquid–liquid equilibrium data were further correlated with the NRTL model successfully.
Section snippets
Experimental
The nonionic surfactant 2-butyloxy-ethanol (C4E1) was an Aldrich Chemical product with a purity of >0.990 and was fractionally distilled under reduced pressure. The purity of the distilled C4E1 was better than mass fraction 0.995 determined by gas chromatography. Octane (C8H18) with a purity of 0.990 was purchased from Alfa Aesar Co. and was used as received. Water was purified by double distillation and then followed by a PURELAB Maxima Series (ELGA Labwater) purification system with the
Results and discussion
Fig. 1 shows the fish-shaped phase diagram of the ternary water + octane + C4E1 system. According to Winsor’s classification [32], phase equilibria of the water + oil + surfactant system can be classified into four types and all these four types of phase equilibria can be found in the fish-shaped phase diagram of the ternary water + octane + C4E1 system, Fig. 1. Inside the fish body, the system exhibits three-liquid-phase-coexisting, identified by 3φ in Fig. 1, that is, the Winsor’s type III phase
Conclusion
The fish-shaped phase diagram and the triangle phase diagram plotted according to liquid–liquid equilibrium data of the water + octane + C4E1 system were performed under atmosphere pressure. The UCST and LCST of the system are 296.90 ± 0.05 K and 286.10 ± 0.05 K, respectively. There is one two- to three- and one three- to two-liquid-phase-coexisting transition when the temperature increases from 283.15 K and 303.15K. The NRTL model can well describe the phase behavior of the water + octane + C4E1 system.
Acknowledgement
This work was supported by the Ministry of Science and Technology of Taiwan.
References (34)
- et al.
Curr. Opin. Colloid Interface Sci.
(2012) - et al.
Fluid Phase Equilib.
(1994) - et al.
Fluid Phase Equilib.
(2004) - et al.
J. Chem. Thermodyn.
(2012) - et al.
Fluid Phase Equilib.
(2013) - et al.
Fluid Phase Equilib.
(2013) - et al.
J. Chem. Thermodyn.
(2003) - et al.
Fluid Phase Equilib.
(2001) - et al.
Fluid Phase Equilib.
(1999) - et al.
J. Chem. Thermodyn.
(2011)
Colloid Science: Principles, Methods and Applications
Microemulsions: Background, New Concepts, Applications, Perspectives
Langmuir
J. Phys. Chem. B
Int. J. Pharm. Sci.
Langmuir
Cited by (6)
Diesel removal and recovery from heavily diesel-contaminated soil based on three-liquid-phase equilibria of diesel + 2-butyloxyethanol + water
2023, Journal of Hazardous MaterialsCitation Excerpt :All of the above characteristics, including the phase equilibrium region distribution and variation tendency, were similar to the literature conclusions regarding the phase behavior of water + surfactant + alkane. The determination of the ternary Gibbs phase diagram could provide guidance for the TPS formulation and control the solution composition within the tie-triangle region to ensure a constant three-liquid phase equilibrium state (Alonso et al., 2020; Chen and Chen, 2015; Pal et al., 2019). In general, fish-shaped phase diagrams are used to describe the phase behavior of microemulsions.
Fish-shaped diagram of liquid–liquid equilibria for the mixtures water + n-alkane + n-alkyl polyglycol ether
2022, Fluid Phase EquilibriaCitation Excerpt :In these measurements, the C4E1 or C6E2 free basis mass fraction of n-octane or n-dodecane, “α”, was changed from 0.1 to 0.9 in order to investigate the change in the behavior of fish-shaped diagrams with the change in α. For the mixtures of water + n-octane + C4E1 and water + n-dodecane + C6E2, the phase diagrams at α = 0.5 have been reported by Andersen et al. [4], Chen and Chen [38], and Hu et al. [32]. Thus, initially, the experimental apparatus and procedures of the fish-shaped diagrams were verified by comparing our experimental data with these literature values.
Phase behavior and interfacial tensions in the ternary systems water + dodecane + propylene glycol n-propyl ether and water + tetradecane + propylene glycol n-propyl ether
2016, Journal of the Taiwan Institute of Chemical EngineersLiquid-liquid equilibrium for the ternary system of isopropyl acetate + 2-propanol + glycerol at different temperatures under atmospheric pressure
2016, Fluid Phase EquilibriaCitation Excerpt :The LLE experiment was carried out in a 30 mL glass cell with a magnetic stirrer in it. The experimental method was described in literature [13–15]. In this study it was specified as follows: The temperature of the system was controlled by a refrigerated heating circulator (Julabo FP45-HF, German, temperature stability ±0.01 K) and measured by a platinum resistance thermometer Pt-100 (calibrated with an accuracy of 0.01 K).
Remediation of diesel-contaminated soil by alkoxyethanol aqueous two-phase system
2022, Environmental Science and Pollution Research