Physical Properties of Ternary Systems Specific Gravities, Refractive Indices, and Changes in Volume on Solution of the System Methyl Alcohol-Isobutyl Alcohol-Water a t 60" F. DONALD M. SMITH,E. I. du Pont de N e m o u r s & Company, Inc., Wilmington, Del. (Ideal vol. % of A ) = (weight This paper indicates a n adaptable and conthe high-pressure synthesis % of A ) C - = (weight %of A ) venient line of attack for the worker who wishes to of organic compounds, it is d, determine precisely and in detail the properties frequently n e c e s s a r y to make of a n undescribed ternary system composed of a c c u r a t e e s t i m a t e s of such physical properties as specific water and two organic liquids, or to interpolate (Actual vol. % of A ) = gravity and refractive index for accurately published data o n such systems. (ideal vol. %of A ) D (9) various s y s t e m s , particularly It also indicates the rather simple relationships solutions of two pure alcohols existing between the various common methods of in water. Systematic s t u d i e s It is evident that, if the obexpressing percentages. The charts obtained by of these physical properties for served specific gravity and the this method can be used to read off precisely the a number of such systems have ratio of observed specific gravity appeared in t h e l i t e r a t u r e : to c a l c u l a t e d specific gravity properties of a given mixture or to pick out methyl alcohol-benzene-water (DIC) are available for a given exactly the composition of a solution f o r which the and ethyl alcohol-benzenes y s t e m , a n y o n e of t h e perproperties are known. The specific gravities, water (1); methyl alcohol-ethyl centages can be readily conrefractive indices, and changes in volume on alcohol-water (2); ethyl verted to the others. solution are determined for the system methyl alcohol-n-propyl alcohol-water, ethyl alcohol-isobutyl alcoholalcohol-isobutyl alcohol-water at 60' F.; the EXPERIMENTAL PROCEDURE water, a n d e t h y l alcoholternary diagrams used to present these data are Figure 1 shows the composii s o a m y l alcohol-water (3); not in error by more than +0.2 per cent, estitions for which specific gravimethyl alcohol-isobutyl alcoholmated in terms of the compositions represented. ties, refractive indices, and the water (4);* a n d e t h y l alcoratio D / C were determined a t hol-ether-water (6). But, in general, the data as presented require interpolations over 60 F. The compositions selected for experiment were taken too wide ranges for the present purposes. I n this paper the to lie on lines of constant isobutyl alcohol-methyl alcohol method is presented whereby detailed charts of the specific ratio ( I / M ) at varying percentages of water ( W ) . The data gravities, refractive indices, and the function D/C (defined for the ratios 10 to 0, 7.5 to 2.5, 5 to 5, 2.5 to 7.5, and 0 to 10 below) of the system methyl alcohol-isobutyl alcohol-water were used in preparing the charts; _the remaining experia t 60" F. were prepared from relatively few experimental points. M I n expressing compositions, volume rather than the customary weight percentages are frequently used. The relations between weight per cent, actual volume per cent, and ideal volume per cent can be derived as follows: Let wa, V b , vC; wo, W b , w,; d., db, d,, be, respectively, the volumes, weights, and densities of the three components A , B, C, making up a solution whose volume, weight, and density are, respectively, V , W , and D , all a t 60" F. Then,
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wa x 100 Vodo x 100 VD wo f w b +wc = va x 100
Weight %of A =
V v, x 100
Actualvol. %of A = Ideal vol. % of A =
Va
+ + vb
Walda
3
(2)
X 100
+ + wc/do (3) + + wc (4)
wa/da
vc
(1)
C=
+ f -+ f $. f we/& + vbdh f vcdc -- wa + f wo V V f f %/da + fweld, vbdb
vodo
va
vb
vcdc
Vc
D = vada
D/C
vo
wa
Wa/da
wb
vb
v
vo
-
OF FIGURE 1. COMPOSITIONS SYSTEM
wb
Wb/db
wb/db
v
(Actual vol. % of A ) = (weight % of A ) D -
da
(5)
(6)
(7)
1 The data of Jlrnecke (4) were uaed in plotting the phaae-equilibrium curve a t 60' F. used in this paper.
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k/
Wb/db
Calcd. density (assuming- no contraction),
THE
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mental points were used in checking the curves and estimating the probable errors. The experimental points also lie on lines of constant water content. The known mixtures were made up of carefully purified components using thermostated Bureau of Standards burets with compositions expressed in ideal volume per cents which were used exclusively in the experimental work reported in this paper; the errors in composition were, in general, less than *0*1 per cent for any component. Specific gravities were measured with sensitive 392
INDUSTRIAL AND ENGINEERING CHEMISTRY
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calibrated hydrometers in a thermostated bath; in each case, readings were readily reproducible to 0.0002, and the average of the several readings, on the whole, did not differ from the true value for the compositions taken by more than *0.0002. (AO.l per cent in composition corresponds to about A0.0002 in specific gravity.) Refractive indices were measured with a Zeiss dipping refractometer in cups contained in a thermostated bath. Readings were readily reproducible to 0.00005; the average was rounded off to the nearest 0.0001 and, in general, did not differ from the true value for the composition taken by more than +0.0001. (AO.1 per cent in composition corresponds a t most to A0.00005 in refractive index.) The ratios of observed to calculated specific gravities ( X loo), @IC) (XlOO), were not in error, on the whole, by more than +0.05 (which could cause errors in converted compositions of not more than *0.05 per cent for any component). The experimental data are presented in Table I.2
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TABLEI. EXPERIMENTAL DATA RATIOI / M Ha0 1/9
2/8
2.5/7.5
%
%
%
100.0 75.0 50.0 25.0 0 75.0 50.0 25.0
0.0 22.5 45.0 67.5 90.0 20.0 40.0 60.0
0
80.0
0.0 2.5 5.0 7.5 10.0 5.0 10.0 15.0 20.0 2.5 5.0 7.5 10.0 12.5 15.0 17.5 20.0 22.5 25.0 7.5 15.0 22.5 30.0 4.0
90.0 80.0 70.0 60.0 50.0 40.0 30.0 20.0 10.0 0
3/7
75.0 50.0 25.0 0
4/6
90.0 80.0 70.0 60.0 50.0 40.0 0
5/5
90.0 75.0 70.0 65.0 60.0 55.0 50.0 40.0 30.0 20.0 10.0 0
7.5/2.5
160REFRACMETHYLBUTYL TIVE SP. GR. ALCO- ALCO- INDEX HOL HOL A T 60" F. AT 60' F.
30.0 20.0 10.0 0
7.5 15.0 22.5 30.0 37.5 45.0 52.5 60.0 67.5 75.0 17.5 35.0 52.5 70.0 6.0 12.0 18.0 24.0 30.0 36.0 60.0 5.0 12.5 15.0 17.5 20.0 22.5 25.0 30.0 35.0 40.0 45.0 50.0 17.5 20.0 22.5 25.0
8.0
12.0 16.0 20.0 24.0 40.0 6.0 12.5 15.0 17.5 20.0 22.5 25.0 30.0 35.0 40.0 45.0 50.0 52.5 60.0 67.5 75.0
1.3334 1.3409 1.3467 1.3464 1.3368 1.3426 1.3497 1.3510 1.3432 1.3370 1.3412 1.3454 1.3487 1.3511 1,3526 1.3534 1,3529 1.3509 1.3466 1.3443 1.3525 1.3554 1.3498 1.3381 1.3434 1.3482 1.3520 1.3552 1.3577 1.3565 1.3387 1.3474 1.3498 1.3521 1.3540 1.3559 1.3577 1.3609 1.3634 1.3860 1.3653 1.3632 1.3729 1.3768 1.3797 1.3801
1.0000 0.9680 0.9.301 0.8745 0.7!370 0.9692 0.9298 0.8745 0.7977 0.9876 0.9761 0.9623 0.9477 0.9291 0.9087 0.8861 0.8602 0.8311 0.7979 0.9696 0.9284 0.8735 0.7981 0.9882 0.9770 0.9622 o.'iiii 0.9066 0.7993 0.9886 0.9700 0.9611 0.9533 0.9444 0.9348 0.9252 0.9050 0.8829 0.8587 0.8317 0.7998 0.8793 0.8565 0.8317 0.8024
RATIO (D/C)
( X 100)
100.00 101.96 103.48
....
99.96 102.06 103.40
. .. .
99.94 100.79 101.70 102.42 103.06 103.29 103.34 103.12 102.54 101.49 99.90 102.08 103.19 99.86 100.84 101.76 102.35
....
103.00 103.02 99.88 100.88
....
102.22
. .. . 102.61 ....
102.72 102.76 102.57 102.12 101.30 99.85 101.95 101.61 101.03 99.84
DISCUSSION OF RESULTS The problem, then, was to convert these data into ternary diagrams showing lines, respectively, of constant specific
* The data of Doroshevskii [ J . Rum. Phys. Chem. Soc., 41, 977 (1909)l and Holmes (in "Alcohol," by Charles Simmonds, Maomillan, 1919) were used in conjunction with some determinations of the present writers for specific gravities and refractive indices at 60° F. of methyl alcohol-water mixtures, and isobutyl alcohol-water mixtures; these data are not included in Table I. The original experimental data quoted in Table I were obtained in May, 1930, by D. M. Smith and W. M. D. Bryant. The carefully purified materials used had physical constants as follows: B. P. SP. GR. REFRACTIVE IND~X SUBSTANCE AT 760 MM. AT 60° F. AT 60" F. Methyl alcohol 64.5' C. 0.7963 1.3304 Isobutyl alcohol 107.4-107.6 0.8060 1.3975 Water 100.0 1.0000 1.3334
FIGURE 2. APPLICATION TO REFRACTIVE INDEXDATA gravity, refractive index and ratio DIC,so that these properties could be read off at any desired composition with a precision as nearly that of the experimental data as possible. I n working up data such as that indicated by Figure 1, the final decision as to methods will obviously depend on the nature of the experimental material, but the procedure used here should be of rather general application for ternary systems containing water and two homologous aliphatic compounds. Figure 2 illustrates the method as applied to the refractive index data. When refractive index at 60" F. is plotted against percentage water for the systems methyl alcoholwater and isobutyl alcohol-water, two divergent curves are obtained, the latter largely interpolated; and, in the absence of other experimental information, lines of constant isobutyl alcohol-methyl alcohol ratio may be interpolated, but the results will be in error by amounts up to about *0.0010. When, in addition, a few representative lines of constant isobutyl alcohol-methyl alcohol ratio (for example, 2.5 to 7.5, 5.0 to 5.0, 7.5 to 2.5) are determined by enough experimental points to draw these curves accurately, the remaining curves can be directly interpolated with a maximum error of about *0.0003. It was found, however, that lines of constant percentage water, drawn from the experimentally determined lines of constant isobutyl alcohol-methyl alcohol ratio, were Telatively simple curves which could be drawn precisely (except for long extrapolations) with very few experimental points. Any desired number of lines of constant percentage water could be drawn, and from them all the lines of constant isobutyl alcohol-methyl alcohol ratio that proved necessary. None of the lines of constant isobutyl alcohol-methyl alcohol ratio so obtained was in error, on the whole, by more than *0.0001 as shown by the fact that nearly all the "confirma-
394
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R*wo
lo+
1“‘ \1” FIGURE4. APPLICATION TO DATAFOR
FIGURE3. APPLICATION TO SPECIFIC G R ~ M T YDATA tory” (as well as the “charted”) experimental points3 lay within +0.0001 of the appropriate curves; a fern points were off by *0.0002, which was consistent with errors of *0.0001 in both the curves and these experimental points. The ternary charts showing lines of constant refractive index were readily drawn by plotting the intersections of constant refractive index lines with this family of curves a t the corresponding percentage of water. The portions of the curves for isobutyl alcohol-water, obtained by long extrapolations of the lines of constant percentage water in this and succeeding figures must not be regarded as exact; they serve, however, to emphasize the trends of the other lines. Figure 3 illustrates the method as applied to the specific gravity data. In thiT case it obviously would be very difficult to draw a family of exact lines of either constant isobutyl alcohol-methyl alcohol ratio or constant percentage water without the use of the procedure described above, or a great many more experimental data. I n Figure 3 lines of constant isobutyl alcoholmethyl alcohol rabio through the charted experimental points are shown at. the lower left while some of the confirmatory points are shown on the appropriate curves a t the lower right. The actual curves used in p r e p a r i n g the ternary diagrams were drawn on a large 8 Charted direct experimental points are indicated on Figures 2 to 4 by plain circles; a few charted points obtained by interpolation from adjacent direct experimental points (not used as confirmatory points) are indicated b y circles with a double tail. Confirmatory experimental points are indicated by circles with a single tail.
P I C ) ( X 100)
scale in greater number than those illustrated and were drawn on several sheets of paper to avoid confusion. By the same type of criteria as used for the refractiye index data, t h e specific gravity curves, in general, were not in error by more than +0.0002. Figure 4 illustrates the method as applied to the data for the ratio (0,C) ( X 100). Here again it would be very difficult to draw directly a family of exact lines of either constant isobutyl alcohol-methyl alcohol ratio or constant percentage water from tl-e few experimental points available. I n Figure 4 lines of constant isobutyl alcohol-methyl alcohol ratio through the charted experimental points are shown a t the lower left while the confirmatory points are shown on the appropriate curves a t the lower right. The lines of constant percentage water for the ratio D C are more difficult to extrapolate than the corresponding lines for specific gravity and refractive index,
DIAGRAMS WITH LINESOF FIGURE 5. TERNARY PROPERTIES
THE
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April, 1934
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INDUSTRIAL AND ENGINEERING CHEMISTRY
so that the hypothetical lines of constant isobutyl alcohol-methyl alcohol ratio in the region of partial miscibility would be best drawn through points obtained by direct calculation from the corresponding lines of observed specific gravity (Figure 3). By the same type of criteria as used for the refractive index and specific gravity data, the curves for the ratio ( D / C ) ( X loo), on the whole, were not in error by more than *0.05.
COHCLUSION Figure 5 shows the general appearance of the ternary diagrams with linerespectively of constant specific gravity, refractive index, and ratio (0, C) ( X 100); and Figure 6 illustrates large-scale detailed charts of the same properties for a portion of the systema4 These F~~~~~ 6, L~~~~ -SCALECHARTSOF PHYSICAL PROPERTIES FOR 4 PORTION OF THE TERNARY SYSTEM charts are designed to be read with an accuracy corresponding to that with which they represent the system. Prepared from large-scale of the ratio D / C could not cause errors in compositions of more drawings, similar to those illustrated in Figures 2 to 4, the than *0.05 per cent. resulting diagrams, in general, were not in error by amounts CITED LITERATURE greater than the corresponding charts of Figures 2 to 4 when (1) Barbaudy, J., Compt. rend., 178, 1279 (1926). judged by the same criteria. Thus, expressed in terms of the (2) Rerl, E., a n d R a n i s , L., Ber., 60, 2225 (1927). corresponding compositions, the lines of constant specific (3) Brun, M. P., Ann. combustibles Ziguides, 7, 635 (1932). gravity and refractive index, on the whole, were not in error, (4) Jdnecke, E., Z . phusik. Chem., 164,401 (1933). respectively, by more than * O . l and +0.2 per cent; and use (5) Sanfourche, A., a n d Boutin, 9.M., BUZZ.soc. chim., 31,546 (1922). I n the original of Figure 6, the cobrdinates are plotted for each 1 per cent, and points can be located to *O.l per cent for each component. 4
RECEIVED September 23, 1933. Presented before the Division of Physical and Inorganic Chemistry a t the 86th Meeting of the .hnerican Chemical Society, Chicago, Ill., September 10 to 15, 1933.
Sulfonic Acids from Petroleum Physico - Chemical Char act eristics E. NEYMAN AND S. PIL.~T, Institute of Petroleum Technology, Lwow, Poland
T
HE sulfonic acids obtained as by-products ( l S , 14, 1;) in petroleum refining are attracting increased attention because of new and better methods of recovering the excess sulfuric acid with which they are mixed and still more because of their increasing use as fat-splitting reagents and for emulsifying oils with aqueous solutions. Of these acids one group of relatively low molecular weight gives water-soluble calcium salts and another of higher molecular weight gives calcium salts insoluble in water. Solubility of the calciuin salts in ether is helpful in separating the acids (15). The characteristics of the three main groups of sulfonic acids are shown in the following table:
other substances in vater and also because they showed strongly those properties ( 1 G ) upon which commercial use of the acids is based. Surface tension determinations showed these salts to be much more effective in decreasing the tension of water than is sodium oleate. The effect of 0.1 per cent solutions mas 65, 51, and 54 for the oleate, alpha salt, and gamma qalt, respectively : S U R F A C E TENSION A G A I N S T A I R BY U S E OF STALAGMOXBTnR ( f 8 ) a
Salt (approx. CnHnS03Xa) MoEe/ D y n e s / lzter cna
y
0.0312 0.0156 0.0078 0.0039 0,0019 0.0009
SULFONIC SOLIJBILITY OF Ca SALTS ACID SOURCE I n water I n ether Alpha Recovered from acid sludge InHoluble Insoluble Beta Recovered from alkali sludge when Insoluble Soluble oil has been treated with fuming acid Gamma Recovered from acid sludge only Soluble Insoluble
a f
The gamma sulfonates can be further divided by means of the water solubility of the barium (of cobalt) salts into two groups. The alpha and gamma classes were studied in this work as they showed the property of affecting the solubility of
b
36.3 39.4 45.4 54.4 64.7 71.7
= -2130 _ c _.
a Salt (approx
Cz8H3oS03Xa) Mole/ Dynes/ later cm 0.0213 41.2 0,0106 43.0 0.0053 46.5 0.0026 48.6 0.0013 55.1 0.0006 61.5 0.0003 63.7
IKTERF4CI.4L T E N S I O N AGAINST
TOLUENE B Y DONNAN METHOD(f) y Na Salt a Na salt soln. soln
’$& C Drops 0.85 310 0,425 181 0.212 128 0.106 87 0.053 83 0.026 79
% C Drops 0.50 218 0.25 181 0.125 143 0.062 114 0.031 95 0
68 toluene drops in water.
Two other properties have been studied-i. e., the effect termed “hydrotropy” (S, 7 , 9, 10, 19) by Neuberg, and the adsorption on activated carbon, silica gel, etc. It is probable that with these substances the lyophile sulfonic group is
