650
HAROLD F. BOGARDUS AXD CECIL C. LYNCH
THE TERKARY SYSTEMS BARIUAI CHLORIDE-DIOXAKE-WATER B?;D CALCIUM CHLORIDE-DIOXANE-’IVA4TER HAROLD F. BOGtlRDUS
AKD
CECIL C . LYNCH
Department of Chemastry, Universzty of Delaware, Newark, Delaware Recezved J u l y 15, 1943
In the further study of ternary systems containing dioxane (6) the systems barium chloride-dioxane-water and calcium chloride-dioxane-water have bern examined. Barium chloride does not appear to form dioxanates, and preliminary investigation indicated no immiscibility in the system; the system should be a simple one. In the case of calcium chloride a monodioxanate has been reported by Heines and Yntema (4), and in preliminary tests we found that immiscibility resulted in the system at high dioxane conrentrntinw PREPARATION O F MATERIALS
Dioxane: Technical 1,4-dioxane from the Eastman Icodak Company was purified by the method described by Eigenberger (3). The product was kept over metallic sodium, from which it vas distilled when needed. Barium chloride: Baker’s C. P. barium chloride mas twice recrystallized from redistilled Jyater, and then dried a t 150°C. for several hours. The anhydrous salt was kept over phosphorus pentoxide in a desiccator. Calcium chloride: A hot saturated solution of Raker’s c. P. calcium chloride (CaC12) was prepared and filtered, and on cooling large crystals of CaClz.6H20 mere obtained. A saturated solution of the salt mas prepared from these crystals and kept at 30°C. This solution was carefully analyzed by titration with silver nitrate (hlohr’s method) and Tyas the source of most of the solutions and mixtures. Some anhydrous calcium chloride n-as prepared by drying over phosphorus pentoxide, and finally fusing in a platinum crucible. Solubility measurements on these salts in water a t 25OC. gave the values: barium chloride, 27.09 per cent by weight and calcium chloride, 45.04 per cent by weight, comparing favorably with the values reported by Bassett, Barton, Foster, and Pateman (1) for barium chloride, and by Bassett, Gordon, and Henshall (2), and Lee and Egerton (5) for calcium chloride. Constant temperature was obtained Tl-ith a water thermostat (25OC. rt 0.05”). 25°C. ISOTHERM FOR THE BARIUM CHLORIDE-DIOXANE-WATER SYSTEM Mixtures of solid phase and mother liquor mere prepared artificially by direct weighing of the three components. The solution in equilibrium with the corresponding solid phase was withdrawn through sintered-glass filters and analyzed for barium chloride by titration with silver nitrate. This method was checked by evaporation to dryness and weighing the residue, with agreement within 1 0 . 3 per cent for all samples tested. The water content was determined by use of the Karl Fischer reagent prepared by the method of Smith, Bryant, and Rlitchell (7). The precision was within f0.3 per cent.
FIQ.1. 25°C. isotherm of the system barium chloride-dioxane-water
FIG.2 . Dioxane corner of the 25%. isotherm of the system barium chloride-dioxane-water 651
TABLE 1 Data for the 25%'. isotherm of the s
( e m barium chloride-dioxane-watev COMPOSITION OF SOLUTION rn. EQUILIBRIUM WIIH SOLU) PHASE
COYPOSlTION OF THE SOLID PHASE-MOTHER LIQUOR MIXTUBE
~
_
_
BaCh
Dioxane
Hn0
BaCli
Dioxane
H90
per cent
per ceiil
per cen
per cent
per rent
per ccnt
46.9 58.2 42.9 35.1 39.4 35.3 33.3 32.6 30.5 26.1 28.8 43.8 16.2 39.4 54.3 45.0 19.1 66.4
1.4 2.1 6.0 10.5 15.5 24.6 28.3 31.0 37.4 43.2 46.4 35.6 62.7 48.2 34.1 46.5 77.6 27.6
51.7 39.7 51.1 50.4 45.1 40.1 38.4 36.4 32.1 31.7 24.8 20.6 21.1 12.4 11.6 8.51 3.30 6.03
26.1 25.0 22.9 20.2 17.0 11. 2 9.51 8.15 5.45 4.48 1.96 1.21 0.64 0.01 0.00 0.00 0.00
1.8 4.0 9.6 15.8 22.6 37.2 41.2 45.6 54.4 58.0 68.7 72.4 76.1 85.9 93.73 98.20 99.05 99.58
____
0.00
72.1 71.0 67.5 64.0 60.4 51.6 49.3 46.2 40.2 37.5 29.3 26.4 23.3 10.1 6.27 1.80 0.95 0.42*
* Equilibrium between two solid phases, BaCI2.2H20and BaCL, and saturated solution. TABLE 2 Data for the 25°C. isotherm of the system calcium chloride-dioxane-water Miscible region (one liquid phase) COMPOSITION OF SOLUTION IN EOUILIBRLUM WITR SOLID PHASE
COMPOSITIOX OF TEE SOLW PHASE-MOTHER LIQUOR MIXTUBE
CaCh
Dioxane
HnO
CaCli
Dioxane
lInO
per cent
per Len1
per cevt
per cent
per cent
per cent
47.4 47.3 44.9 43.6 42.2 41.8 39.7 38.3
0.6 2.9 13.7 16.3 18.9 19.7 23.6 26.2
52.0 49.8 41.4 40.1 38.9 38.5 36.7 35.5
44.8 44.5 43.9 41.6 39.8 39.1 36.5 33.8
1.3 2.5 3.7 7.3 10.0 11.1 15.0 19.7
53.9 53.0* 52.4 51.1 50.2 49.8 48.5 46.5
____
Immiscible region ( t w o liquid phases)
!
COMPOSITION OP LIOBTER LAYER
1
H~O
CaCh
Dioxane
per u n l
per cent
per cent
27.9 32.8 40.2 54.0
43.5 47.9 47.0 39.6
28.6
;;:! 6.41
I ~
1
COMPOSITION OF HEAVIER LAYER
CaC19
Dioxane
Ha0
fier cent
per rent
per L e d
0.00 0.00 0.05 0.99
98.54 95.98 92.71 80.5
1.46t 4.02 7.24 18.5
TERNARY SYSTEMS CONTAINING DIOXANE
653
The data for this isotherm are given in table 1 and in figures 1 and 2. The isothermaIly invariant point was determined from three different mixtures (indicated by the crosses) and the average value ig given. It should be noted that the dihydrate is stable over most of the range of dioxane concentration, and only above 99.58 per cent dioxane is the anhydrous salt the equilibrium solid phase. 25°C. ISOTHERM FOR THE SYSTEM CALCIUM CHLORIDE-DIOXANE-WATER Mixtures of solid phase and mother liquor were prepared artificially by direct weighing of the three components or by use of the saturated aqueous solution of
FIQ.3.
25'C. isotherm for the system calcium chloride-dioxane-water
calcium chloride referred to above. Analysis was made aa described under the barium chloride-dioxane-water system. In the immiscible region, mixtures of approximate composition were prepared, and each layer was analyzed for calcium chloride and water as before. Data for the isotherm are given in table 2 and in figure 3. The isothermally invariant points were determined in triplicate and the average value is included in the table. Region I is an area in which CaC12.6Hz0is the equilibrium solid phase; region I1 is one where the solvate CaClz.(CSH&O2.2 HzO is the solid phase in equilibrium with the saturated solution; and region I11 is the immiscible portion of the system. The region beyond 98.5 per cent dioxane was not investigated.
654
HAROLD F. BOGARDUS A N D CECIL C. LYNCH
The solvate CaCl2.(CzH&09.2Hz0 was separated from solution and dried over a mixture of an excess of this solvate and some partially desolvated material in a desiccator. This was continued over a period of 3 months, until no further change in mass resulted. No decomposition of the crystals was indicated during the process. Analysis of these crystals for water and calcium chloride gave the following results: TEEORETICAL POX
EXPEP1mNTAL
___
)Lf
Calcium chloride. . . . . . . . . . . . . . . . . . . . . . . Dioxane. . . . . . . . . . . . . . . . . . . . . . . Water.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
cent
47.2 37.3 15.5
CaCIv ( C H ~ O O P Z H ~ O )cr c c d
47.22 37.45 15.33
REFERENCES BASSETT, BARTON, FOSTER, AND PATEMAN: J. Chem. Soc. 1933, 151. BASSETT, GORDON, AND HENSHALL: J. Chem. SOC.1937, 971. EIGENBERGER: J. prakt Chem. 130, 75 (1931). HEINESAND YNTEMA: Trans. Kmtucky Acad. Sci 7 , 55 (1838); Chem. Abstracts 36, 1717 (1941). LEE AND EGERTON: J. Chem. Soc. 123, 706 (1023). LYNCH: J. Phys Chem. 46, 366 (1942). SMITH, BRYANT A N D MITCHELL: J. Am. Chem. Sac 61,2407 (1939).
