Liquid–liquid equilibria for the ternary system (water+hexadecane+dipropylene glycol n-propyl ether)

Abstract

a b s t r a c tThe fish-shaped phase diagram of the ternary system (water + hexadecane + dipropylene glycol n-propyl ether) under atmospheric pressure was performed at constant water/hexadecane mass ratio (1/1). The upper critical solution temperature of the ternary system was determined as 314.00 K. Liquid + liquid equilibria of the system were measured at T = 298.15, 308.15, and 318.15 K under atmospheric pressure. The experimental data of liquid-liquid equilibria were further correlated with the NRTL model.

Liquid–Liquid Equilibria for the Ternary System Water + Dodecane + 1-(1-Methyl-2-propoxyethoxy)-2-propanol

“…It is well understood that the glycol ether mainly dissolves in the oil-rich phase when the system temperature is above its UCST. [1][2][3][4][5]7,9 The experimental equilibrium compositions of the ternary system water + dodecane + C 3 P 2 at (288.15, 298.15, and 308.15) K are given in Tables 1, 2, and 3, respectively. The LCST of the binary water + C 3 P 2 system is 283.15 K, 3 and the water + C 3 P 2 mixture is not completely miscible at these three temperatures.…”

“…The ternary mixtures with different C 3 P 2 mass fractions were prepared under the condition of constant water to dodecane mass ratio at 1:1. All samples sealed in test tubes were mixed completely and then were put in a homemade thermostat − (its temperature was controlled within ± 0.005 K) to allow the samples for equilibration under a prescribed temperature. When the system reached equilibrium, liquid phases were thoroughly transparent, and interfaces were very sharp and looked like a mirror.…”

“…The experimental procedure of triangle phase diagrams followed our previous works closely. − After the equilibrium of the ternary mixture was reached, each liquid phase was sampled by the syringe and injected to the gas chromatography with the thermal conductivity detector (GC-8A, Shimadzu Co., Japan). The operating temperatures of the detector and the sample injector were both set at 563.15 K. The oven temperature was 493.15 K. The sample was isothermally carried by helium with a constant flow rate of 0.50 mL·s –1 and separated in a 2 m long stainless steel column stuffed with the Poropak P 80/100 mesh packing.…”

“…The experimental data of the phase equilibrium are necessary when we design these unit operations which are used to separate mixtures. Recently, we have investigated three ternary water + oil + 1-propoxy-2-propanol (also known as propylene glycol n -propyl ether, abbreviated by C 3 P 1 ) systems, − where the symbol C i P j is the abbreviation of nonionic surfactant polyoxypropylene alcohol CH 3 (CH 2 ) i −1 (OCH 2 CH(CH 3 )) j OH. The upper critical solution temperature (UCST) and the lower critical solution temperature (LCST) of the water + alkane + C 3 P 1 system increase with the increasing oil chain length .…”

Liquid–Liquid Equilibria for Systems of Ethanol + Octanol + Nonanol + Dodecane + Tridecane + Water at Different Temperatures under Atmospheric Pressure

“…Liquid–liquid equilibria (LLE) data is the foundation of extraction. LLE data of systems containing higher alcohols + higher hydrocarbons + water or ethanol have been studied in recent years. − However, the LLE data related to ethanol (1) + octanol (2) + nonanol (3) + dodecane (4) + tridecane (5) + water (6) has not been reported. In this work, experimental liquid–liquid equilibria data of four quaternary systems {ethanol (1) + octanol (2) + dodecane (4) + water (6)}, {ethanol (1) + octanol (2) + tridecane (5) + water (6)}, {ethanol (1) + nonanol (3) + dodecane (4) + water (6)}, and {ethanol (1) + nonanol (3) + tridecane (5) + water (6)} were determined at T of 293.15, 298.15, and 303.15 K and P of 101.3 kPa.…”