IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

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 Solubility System: 2-Propanol with Toluene and Water

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Components:
   (1) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail
   (2) 2-Propanol (isopropanol, isopropyl alcohol); C3H8O; [67-63-0]  NIST Chemistry WebBook for detail
   (3) Toluene (methylbenzene); C7H8; [108-88-3]  NIST Chemistry WebBook for detail

Original Measurements:
   Washburn, E.R.; Beguin, A.E., J. Am. Chem. Soc. 62, 579 (1940).

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	Mass Fraction w2	Mole Fraction x1 (compiler)	Mole Fraction x2 (compiler)
25.0	298.15	0.0425	0.0013	0.0131	0.0003
25.0	298.15	0.1076	0.0018	0.0349	0.0004
25.0	298.15	0.1650	0.0030	0.0561	0.0007
25.0	298.15	0.2340	0.0038	0.0842	0.0009
25.0	298.15	0.3016	0.0107	0.1159	0.0027
25.0	298.15	0.3438	0.0188	0.1385	0.0049
25.0	298.15	0.3944	0.0422	0.1714	0.0120
25.0	298.15	0.4364	0.0675	0.2044	0.0206
25.0	298.15	0.4753	0.1074	0.2453	0.0362
25.0	298.15	0.4957	0.1413	0.2756	0.0512
25.0	298.15	0.5101	0.1827	0.3084	0.0720
25.0	298.15	0.5117	0.2255	0.3333	0.0958
25.0	298.15	0.5089	0.2773	0.3627	0.1289
25.0	298.15	0.4961	0.3350	0.3882	0.1710
25.0	298.15	0.4814	0.3736	0.3983	0.2016
25.0	298.15	0.4559	0.4270	0.4052	0.2475
25.0	298.15	0.4255	0.4709	0.3946	0.2848
25.0	298.15	0.3905	0.5263	0.3861	0.3394
25.0	298.15	0.3430	0.5928	0.3634	0.4097
25.0	298.15	0.2745	0.6872	0.3228	0.5270
25.0	298.15	0.2176	0.7550	0.2715	0.6144
25.0	298.15	0.1597	0.8243	0.2127	0.7162
25.0	298.15	0.1064	0.8848	0.1493	0.8096
25.0	298.15	0.0431	0.9530	0.0636	0.9172

Compositions of coexisting phases

t/°C	T/K	Mass Fraction w1	Mass Fraction w2	Mole Fraction x1 (compiler)	Mole Fraction x2 (compiler)	Comment(s)
25.00	298.15	0.0089	0.9911	0.0136	0.9864	hydrocarbon-rich phase
25.00	298.15	0.0227	0.9764	0.0343	0.9612	hydrocarbon-rich phase
25.00	298.15	0.0745	0.9184	0.1069	0.8592	hydrocarbon-rich phase
25.00	298.15	0.1434	0.8430	0.1942	0.7444	hydrocarbon-rich phase
25.00	298.15	0.2490	0.7190	0.3019	0.5686	hydrocarbon-rich phase
25.00	298.15	0.3062	0.6435	0.3426	0.4696	hydrocarbon-rich phase
25.00	298.15	0.3790	0.5420	0.3805	0.3549	hydrocarbon-rich phase
25.00	298.15	0.4423	0.4435	0.3976	0.2600	hydrocarbon-rich phase
25.00	298.15	0.4857	0.3635	0.3962	0.1934	hydrocarbon-rich phase
25.00	298.15	0.4995	0.3260	0.3859	0.1643	hydrocarbon-rich phase
25.00	298.15	0.5100	0.2716	0.3602	0.1251	hydrocarbon-rich phase
25.00	298.15	0.5105	0.2640	0.3558	0.1200	hydrocarbon-rich phase
25.00	298.15	0.5120	0.2356	0.3396	0.1019	hydrocarbon-rich phase
25.00	298.15	0.0687	0.0001	0.0216	0.0000	water-rich phase
25.00	298.15	0.1216	0.0030	0.0400	0.0006	water-rich phase
25.00	298.15	0.1977	0.0028	0.0690	0.0006	water-rich phase
25.00	298.15	0.2414	0.0052	0.0875	0.0012	water-rich phase
25.00	298.15	0.2900	0.0102	0.1102	0.0025	water-rich phase
25.00	298.15	0.3140	0.0125	0.1222	0.0032	water-rich phase
25.00	298.15	0.3434	0.0146	0.1377	0.0038	water-rich phase
25.00	298.15	0.3740	0.0296	0.1570	0.0081	water-rich phase
25.00	298.15	0.3992	0.0433	0.1745	0.0123	water-rich phase
25.00	298.15	0.4210	0.0558	0.1911	0.0165	water-rich phase
25.00	298.15	0.4413	0.0709	0.2087	0.0219	water-rich phase
25.00	298.15	0.4473	0.0847	0.2167	0.0268	water-rich phase
25.00	298.15	0.4650	0.0950	0.2331	0.0311	water-rich phase

Method/Apparatus/Procedure:
   The titration method, as described in Ref. 1, 2, was used. Refractive indexes of mixtures were measured by Abbe refractometer. Binary mixtures of known composition placed in small Erlenmeyer flasks were titrated with water or toluene from weighed pipettes and shaken mechanically in a constant temperature bath. Measured refractive indexes of saturated solutions were plotted for each component. These plots were used further to determine concentration of equilibrium  phases. Tie lines were obtained by adding alcohol to water-toluene mixtures and shaking the samples from time to time during the twenty-four hours while they were kept in constant temperature bath. After separation, refractive indexes of both phase were measured and concentration of each component was read from the plots. The sum of calculated phase concentrations was always equal to 1.0000±0.0001.

Source and Purity of Materials:
   (1) Eastman Kodak Company; refluxed with CaO, distilled, middle fraction was used; b.p.=81.7-81.9°C, d(25°C,4°C)=0.780 87, n(25°C,D)=1.3748.
   (2) Eastman Kodak Company; used as received; n(25°C,D)=1.4938.
   (3) Distilled over KMnO₄.

Estimated Errors:
   Solubility: Not reported.
   Temperature: Temp. ±0.01°C.

References:
   ¹ R. Vold and E. R. Washburn, J. Am. Chem. Soc. 54, 4217 (1932).
   ² E. R. Washburn and H. C. Spencer, J. Am. Chem. Soc. 56, 361 (1934).

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