IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

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 Solubility System: Ethanol with Cyclohexane and Water

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Components:
   (1) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail
   (2) Cyclohexane; C6H12; [110-82-7]  NIST Chemistry WebBook for detail
   (3) Ethanol (ethyl alcohol); C2H6O; [64-17-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Plackov, D.; Stern, I., Fluid. Phase Equilib. 71, 189 (1992).

Variables:
   Temperature = 298 K

Prepared By:
   A. Skrzecz

Experimental Data:   (Notes on the Nomenclature)
  

Compositions along the saturation curve

t/°C	T/K	Mass Fraction w1 (compiler)	Mass Fraction w2 (compiler)	Mole Fraction x1	Mole Fraction x2
25	298.2	0.0243	0.9744	0.0433	0.9506
25	298.2	0.0614	0.9360	0.1058	0.8826
25	298.2	0.1157	0.8781	0.1890	0.7851
25	298.2	0.1913	0.7976	0.2915	0.6653
25	298.2	0.2697	0.7125	0.3824	0.5531
25	298.2	0.3426	0.6324	0.4553	0.4600
25	298.2	0.4187	0.5476	0.5204	0.3726
25	298.2	0.4703	0.4891	0.5588	0.3181
25	298.2	0.5285	0.4206	0.5945	0.2590
25	298.2	0.5960	0.3347	0.6230	0.1915
25	298.2	0.6215	0.2987	0.6284	0.1653
25	298.2	0.6814	0.1908	0.6125	0.0939
25	298.2	0.6867	0.0877	0.5235	0.0366
25	298.2	0.6024	0.0299	0.3864	0.0105
25	298.2	0.5258	0.0138	0.3073	0.0044
25	298.2	0.4538	0.0070	0.2471	0.0021
25	298.2	0.3788	0.0029	0.1931	0.0008
25	298.2	0.3090	0.0019	0.1491	0.0005
25	298.2	0.2419	0.0016	0.1111	0.0004
25	298.2	0.1685	0.0008	0.0735	0.0002
25	298.2	0.0811	0.0009	0.0334	0.0002

Compositions of coexisting phases

t/°C	T/K	Mass Fraction w1 (compiler)	Mass Fraction w2 (compiler)	Mole Fraction x1	Mole Fraction x2	Comment(s)
25	298.2	0.002	0.998	0.003	0.994	hydrocarbon-rich phase
25	298.2	0.004	0.996	0.007	0.990	hydrocarbon-rich phase
25	298.2	0.008	0.991	0.015	0.982	hydrocarbon-rich phase
25	298.2	0.012	0.988	0.021	0.976	hydrocarbon-rich phase
25	298.2	0.018	0.981	0.032	0.964	hydrocarbon-rich phase
25	298.2	0.029	0.970	0.051	0.943	hydrocarbon-rich phase
25	298.2	0.134	0.000	0.057	0.000	water-rich phase
25	298.2	0.280	0.000	0.132	0.000	water-rich phase
25	298.2	0.413	0.010	0.218	0.003	water-rich phase
25	298.2	0.506	0.013	0.290	0.004	water-rich phase
25	298.2	0.601	0.015	0.377	0.005	water-rich phase
25	298.2	0.677	0.024	0.465	0.009	water-rich phase

Method/Apparatus/Procedure:
   Binodal compositions were determined by titration with the corresponding, less-soluble component until the appearance of turbidity, Ref. 1. The analytical method was used for determination of tie-lines. This was based on refractive indexes and densities of the samples, Ref. 1, combined with the oxidation of the alcohol with an excess of potassium dichromate and determination of unreduced dichromate with Na₂S₂O₃.  Alcohol in the organic layer was determined after extraction with water.

Source and Purity of Materials:
   (1) Kemika (Zagreb); analytical grade; presumably used as received; n=1.3593, p(25°C)=787.0 kg/m³, b.p.=79.1°C.
   (2) Kemika (Zagreb); purity not specified; presumably used as received; n=1.4232, p(25°C)=773.9 kg/m³, b.p.=80.0°C.
   (3) Twice distilled in the presence of KMnO₄.

Estimated Errors:
   Solubility: Not reported.
   Temperature: Composition < 0.005 mass fraction, binodal, (relative); composition ± 2%, tie line.

References:
   ¹ D. Plackov and I. Stern, Fluid Phase Equilib. 57, 327 (1990).

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Last updated: February 18, 2015 (Created: August 17, 2007)