Solvent Extraction of Tar Acids from Coal Tar Hvdrocarbons J
C. F. PRUTTON', T. J. WALSH, AND A. M. DESA12 Case Znstitute of Technology, Cleveland 6, Ohio Data are presented on the solubility of typical tar acids and hydrocarbons in mixed water-methanol solvents at temperatures of loo, 25O, and 35" C. The tar acids included are phenol, p-cresol, 2-naphthol, and p-tert-butylphenol. The hydrocarbons considered are methylnaphthalene, hexadecane, and 2,2,4-trimethylpentane. t
100% METHANOL
100% PHENOL,
100% W
AlF R
Figure 1. Equilibrium Relations for System 1 Water-methanol-phenol, Temperature 25' C.
100% M E T H A N O L
._--
S
OLVENT extraction is an operation useful in separating mixtures of materials according to their chemical nature where other methods of separation, such as distillation, are incapable of the separation desired. To be economically practical a solvent should possess a high solvent power and a high selectivity (4). These requirements are often unavailable in a single solvent, and many processes use double or triple solvents to secure the combination of properties desired for the extraction. Coal tar is a mixture of compounds that cannot be separated by simple means. Some form of extraction is necessary to separate the phenolic compounds from the hydrocarbons and other materials found in the tar. The extraction may be with sodium hydroxide solution, or by other solvents, among which are the double solvents of an alcohol and water. The Metasolvan proces5 (6) developed in Germany effected a partial separation using an ethanol-water mixture as a solvent. The process design actually called for the use of methanol-water mixtures in concentrations ranging from 60 to 90% methanol by volume, but the ethanol had been substituted in the pilot plants owing to its greater availability in Germany during the war years. Preliminary tests showed that the methanol-water mixtures were a better solvent than either the ethanol mixtures or any of the other solvents normally found in a chemistry laboratory. The results of extraction studies with methanol-water mixtures as a solvent for various hydrocarbons and phenols such as are found in coal tar are reported herein. To reduce the experimental work connected with the investigation, two quaternary systems were studied in detail. The information obtained with these systems was used to interpret the
p-CRESOL
WATER
1
Present address, Mathieson Chemical Corporation, Baltimore, Md. Present addreas, University of Bombay, Bombay, India.
Figure 2. Equilibrium Relations for System 2 Watsr-methanol-p-orsol.
Temperaturs 35' C .
100% METHANOL
NOTE: T I E L I N E S SHOWN F O R 25%. ONLY
100%
FIG. 3 EQ UI L IB R I U M RELATIONS SYSTEM 3
PHENOL
FIG. 4 E Q UlLl B R IUM RELATIONS SYSTEM 4 METHYLNAPHTHALENE
NAPHTHALENE
TEMPERATURE
IO&
WATER
100% M E T H Y L ' NAPHTHALENE
1210
lune 1950
1211
INDUSTRIAL A N D ENGINEERING CHEMISTRY METHANOL
100%
EQUILIBRIUM RELATIONS
c
NAPHTHALENE TEMPERATURE
'WATER
PHENOL W
Figure 6, Diagrammatic Representation of System 8 100% PHENOL
FIG. 7
NOTE: F I Q U R E S SHOW % METHANOL I N SOLVENT
METHANOL
SYSTEM 8 METHANOL
EQUILIBRIUM
NAPHTHALENE EM PERATUR E
WATER
100% WATER-
v v v v
ME THAN 0 I_
\/
v //A 100% M E T H Y L NAPHTHALENE
p - CRESOL
100 % p- CRESOL
N F IOGTUER. E S S H O W
A
Figure 9. EquilibriumRelations and Phase Zone Boundaries Water-mothawl-methylnspbthslensp-cresol. Temperature 35' C.
Figure 8. Diagrammatic Representation of System 9
100% PHENOL
/f\
FIG. IO EQUILIBRIUM
1212
INDUSTRIAL AND ENGINEERING CHEMISTRY t
Vol. 42, No. 6 k
100% P H E N O L
100% P H E N O L
100% HYDROCARBON
100% SOLVENT
Figure 11. Equilibrium Relations for System 11 70% methanol, 30% waterdO% methylnaphthalene, 40% 2,2,4-trimethylpentane-phenol. Temperature 35' C.
HYDROCARBON 100%
100% SOLVENT
Figure 12. Equilibrium Relations for System 12 70% methanol 30% water43.4% methylnaphthalene 56.6% 2.24-
trimhylpentane-phenol.
100%
Temperature 35°C.
t
p- C R E S 0 . L
100% P - C R E S O L
SOLVENT
M E 1 HY L N A P H T H A L E N E
Figure 14. Equilibrium Relations for System 14 70% methanol, 30% water-methylna hthalene-p-cresol
8.
0 Temperature 35' A Temperature IOo C.
caustic-insoluble fraction, and the phenol by bromination of the caustic extract. The methanol was determined by difference.
Figure 13. Equilibrium Relations for System !3 70% methanol, 30% water-60% meth Inaphthalene, 40% 2,2,&tri-
methylpentane-p-cresol.
dmperature 3 5 O C.
data from abbreviated studies with other compounds. The quaternary systems are: methanol-water-phenol-methylnaphthalene and methanol-watery-cresol-methylnaphthalene. Other compounds included in the abbreviated studies are hexadecane, 2,2,4trimethylpentane, 2-naphthol, and p-tertbutylphenol. ANALYTICAL PROCEDURES
Where equilibria data are reported, the compositions of the equilibrium mixtures were determined by direct analysis. This gave not only the binodal curve but also the compositions of the phases in equilibrium. Samples were brought to equilibrium by mounting &ounce oil sample bottles on a rotating wheel in an Aminco constant temperature bath. The temperature was held to 0.01" C. by controlling automatically one heating circuit in the bath. The other circuit and a stream of cooling water were first adjusted to give continuous cooling effect when the first heater waa not operating. Rotation of the wheel inverted the sample bottles every 30 seconds. Samples were agitated in the bath at constant temperature overnight (at least 12 hours) before the phases were separated. Phase samples were taken without removing the bottles from the constant temperature bath by withdrawing part of each phase with a rubber bulb pipet. Water W M determined by Karl Fischer reagent (a), using the A.S.T.M. recommended procedure ( I ) , hydrocarbons as the
The abbreviated analysis consisted in determining the causticinsolubles and the phenol in an equilibrium mixture, The remainder of the system was called solvent. This was done for a series of mixtures starting with the same solvent cbntaining 70% methanol by weight. When necesswy to distinguish between two hydrocarbons in the caustic-insoluble fraction, refractive index was used. A calibration chart was determined for this procedure by preparing samples of known composition from caustic-washed pure hydrocarbons. As most phenols do not brominate quantitatively (6),a standard procedure was set up and calibrated using known quantities of each phenol to be investigated. Results showed that although the bromination was not complete, in many cases the degree of bromination was constant for a given set of conditions and could be used for analysis. Even though two operators follow the same written procedure, there is enough difference in their techniques to justify each operator's development of his own calibrstion curve. Generally the composition of the solvent was not the same in each of the two phases existing in an equilibrium mixture. Therefore, when i t was desired to study a plane having a fixed methanol-water ratio or a fixed methanol content, other techniques had to be used. These were either turbidimetric with visual recognition of the end point or refractometric using a modification of the method described by Rutzler and Rauman (7). The refractive index technique for locating a binodal curve worked very nicely in its application to liquid-liquid system. A mixture of known composition in the one phase region is prepared and divided into several portions of known volume. To
INDUSTRIAL AND ENGINEERING CHEMISTRY
lune 1950
1213
t
I
100% 8 - N A P H T H O L
100% p - C R E S O L c
100%
100% SOLVENT
M E THYLNAPHTHALENE
Figure 16. Equilibrium Relations for System 16 Figure 15. Equilibrium Relations for System 15
70 % methanol, 90 % wate~methylnaghthalen~2-naphthol.T ~ I D I -
peratwe35 C.
60% methanol, 40 % water-methylnaphthalenep-ereaol. Temperature $5' C. 100%
4 p - TERTIARY
E Q U lL l B R IUM RELATIONS SYSTEM 18
EUTYLPHENOL
HEXADECANE I""r0
METHYLNAPHTHALENE
SOLVENT
.E MPERATURE
Figure 17. Equilibrium Relations for System 17 70% methanol, SO % watermethylnaphthalen~ptert-butylphenol. Temperature 35O C.
100%
EQUILIBRIUM R E LATlON S SYSTEM 19
100% SOLVENT
HEXAOECANE
H.E X A DE CAN E MPERATURE
SOLVENT
HEXAOECANE
Figure 20.
m
each of these is added a known quantity of the component that lies across the binodal curve in the conventional triangular representation of the system. The mixtures are then brought to equilibrium a t the desired temperature. Some will consist of only one phase and others will consist of two phases. The refractive index of each phase present in the samples is measured a t some temperature such that no change in the phase composition will occur during the analysis. If convenient, this may be the equilibrium temperature. The refractive index is plotted against the quantity of added component. A smooth curve results as long as only one phase is present. With the appearance of the second phase, a sharp break occurs in the curve and it separates into two branches. One branch may be extrapolated backward to meet the extension of the single phase curve. The junction of
HEXADECANE
S 0 LV E N T
Equilibrium Relations for System 20
70% methanol, 30 % water-hexadecane-2-naphthol. Temperature $50 c.
these curves indicates the exact quantity of the third component that should have been added just to cause the appearance of the second phase. This oan easily be determined to 0.01 ml. The composition of the desired mixture can now be calculated on a weight per cent basis from the quantities of materials in the starting mixture and the added component. CHEMICALS
The methanol used in this investigation was Baker's C.P. analyzed absolute methanol. This was reported to contain 99.6%
INDUSTRIAL AND ENGINEERING CHEMISTRY
1214
100% p - TERTIARY BUTYLPHENOL
Vol. 42, No. 6
100% HEXADECANE
FIG. 21 E Q U l LI B R I U M RELATIONS
FIG. 2 2 EQUILIBRIUM R EL AT IO N S S Y S T E M 22
HEXADECANE NAPHTHALENE
BUTYLPHENOL EMPERATURE
TEMPERATURE
METHYLNAPHTHALENE
SOLVENT
100% HEXADECANE
m
FIG. 23 EQ UI L I B R IUM RELATIONS SYSTEM 2 3
This material appeared identical on physical testa with Eastman Kodak C.P. phenol. All other chemicals used in this study were the purest grade obtainable from the Eastman Kodak Company and were used without further purification. EQUILIBRIUM DATA
NAPHTHALENE
Data we presented in Table I and in Figures 1 to 23 for the following systems:
E MPERATURE 1. Water-methanol-phenol
2. 3. 4. 5. 6, 7. 8. 9. SOiCi-NT
100% METHYLNAPHTHALENE
lo.
Water-methanol-p-cresol Water-methanol-meth lnaphthalene Water-methylnaphtha3kne-phenol Water-methylnaphthalene-p-cresol Methanol-methylnaphthalene-phenol Methanol-meth lnaphthalene Water-methano~-phenol-meth&~f~~alene Water-methanol-p-cresol-methylnaphthalene
i!g
~~~~~ol)-methylnaphthalene-phenol
70% methanol - 60% methylnaphthalene 30% water (40% 2,2,4-trimethyIpentane)-p11eno~ 12. 70% methanol 43.4% methylnaphthalene }-phenol 30% water 56.6% 2,2,4-trimethylpentane 13. 70% methanol 60% methylnaphthalene 30% water )-(40% 2,2,4-trimethylpentane)-pcreso1 11.
methanol and a check with Karl Fischer reagent showed the sample to be water-free. Two types of methylnaphthalene were used. Type I was Eastman Kodak 1-methylnaphthalene, which distilled at 238" t o 240" C. and is estimated t o contain about 5% of the 2methylnaphthalene isomer. Type 2 was prepared from crude methylnaphthalene which was purchased from the Reilly Tar and Chemical Company. The crude material was extracted twice at 50" C. with its own weight of 20% sodium hydroxide, solution to remove any caustic-soluble fractions in the methylnaphthalene. The stock waa then heated to 120" C. to drive off any emulsified water. Five per cent by weight of sodium was added and the mixture was refluxed for 2 hours. The mixture wm then distilled and the fraction boiling at 240" C. was collected for use. This product was a pale yellow liquid with practically no odor. The methylnaphthalene so prepared could be kept indefinitely if protected from both light and air. Exposure to either results in a darkened product with the odor generally associated with methylnaphthalene. Although this methylnaphthalene was estimated to contain about 10% 2-isomerJ very little difference could be observed between this and the Eastman l-methylnaphthalene. Dow phenol was distilled to give a water-white crystalline product, which was wed until it began t o show a tinge of pink.
} )-{
14*
:g
15.
60 40$ methanol) water -methylnaphthalene-p-cr~ol
lG. 17*
'** 19.
i:g i:g
~~~~~l)-methylnaphthalene-p-cresol
~~~~~l}-methylnaphthalene-p-naphthol
~~~'~l)-methylnaphthalene-ptw~-butylphenol ~~~~~o~)-hexadecane-p-cresol
"%
20% water
-hexadecane-p-crmol
20. 709 3 0 g water methano1)-hexadecane-2-naphthol 21'
;!g
~~~~l]-hexadecan~tertbutylphenol
22* 709 30% methanol)-methylnaphthalene-hexadecane water
23.
!tg
~~~~~O1]-methylnaphthalene-hexadecane
Data for a11 systems are reported in weight per cent.
INDUSTRIAL A N D ENGINEERING CHEMISTRY
June 1950
1215
TABLE I. EQUILIBRIA AND PHASE BOUNDARY DATA (All data are in weight per cent) P h b I1 Component A A B C
P k e I Component A
B
C
SVtom 1. Component A Water Component B Methanol. Component C, Phenol. Temperature 26' C. 8.4 0.0 71.3 0.0 28.7 1.2 8.9 68.7 1.6 81.7 2.2 9.8 64.4 2.8 82.8 10.8 4.8 57.9 4.7 87.4 11.8 8.8 49.6 7.7 48.8 17.4 11.1 40.0 10.0 50.0 23.6 12.8 35.3 11.8 66.2 26.0' 12.8O 81.4a
..
..
.. ..
.. ..
....
..
System 3. Com onent A Water
onent B Methanol. 2 Methydaphthdens.Com&mperat;re 26' 0.
0.0 0.0 0.0 0.0 0.0 0.0
..
.... I
.
0.0 1.0 1.2 1.8 2.6 8.0
*. *. .. *.
100.0 99.0 98.8 98.2 97.6 97.0 *.
.. .. a .
j
100.0 80.0 48.2 24.0 18.0 13.8 7.8 6.3 3.4 2.2
0.0 40.0 68.8 78.0 76.6 76.2 72.8 72.0 58.0 53.0
Component
11.0 19.8 21.7 38.6 44.8
Temperature 35O C.
Syatem 4.
0.0 1.9 6.0 14.6 18.1 28.7 System 5. 0.0 0.1 0.8 2.0 4.8 6.2 10.2 18.8
Component A Water. Component B Methylnaphthalene. Component b, Phenol. Temperature 'aso C. 100.0 0.0 0.0 0.0 100.0 0.0 98.2 3.8 28.8 71.3 93.7 6.3 0.0 42.0 62.0 0.0 93.0 7.0 55.5 80.0 7.8 92.2 0.0 62.0 19.9 91.6 8.4 0.0 71.3 0.0
17.6 20.4 22.5 26.7 0.3 0.8 3.5 5.8 9.0 13.2 18.8 19.8 21.1 29.6
Concentration of Solvent, 70% Methanol 0.7 0.0 99.0 1.6 11.7 88.2 8.4 21.8 86.8 18.2 26.8 54.4 41.0 21.0 29.0 27.4 30.6 28.8 19.0 38.1 26.6 12.0 45.6 22.8 49.5 19.7 9.7 89.0 1.5 0.0
1,.0 2.1 11.9 18.8 30.0 43.8 64.4 65.2 70.6 98.5
Concentration of Solvent, 62.4% Methanol 0.8 0.0 99.0 1.0 0.7 90.5 ... 1.1 7.7 1.8 14.6 83.2 0.9 1.4 2.3 8.6 19.2 76.2 2,l 5.8 23.6 417 68.8 2.9 7.6 27.2 63.0 3.7 9.8 8.1 4.6 29.8 12.8 7.7 57.9 81.7 16.6 10.3 5.2 61.8 9.0 31.6 24.0 16.0 44.6 31.0 21.2 36.0 12.8 84.0 30.0 22.0 18.0 80.0 48.0 24.2 10.4 24.7 40.7 66.4 27.8 46.7 78.3 20.6 8,2 16.2 30.5 3.8 81.0 50.6 34.0 90.4 68.4 1.6 8.0 87.6 82.1 0.4 99.8 0.0 System 9. Com onent A Water Component B Methanol. Component C, pcreool. 8omponedt D, Mithylnaphthalend. Temperature 36O C. Plane Containing 20.0% Methanol 20.6 0.0 79.4 0.8 20.0 66.3 22.7 2.7 20.0 11.0 3.9 20.0 80.7 23.9 16.4 6.9 20.0 22.5 61.6 26.9 26.9 46.4 27.7 7.7 20.0 28.9 28.7 42.4 8.9 20.0 10.6 20.0 34.9 34.5 30.6 28.4 33.6 20.0 40.2 13.6 46.1 17.2 37.7 17.7 20.0 9.0 42.4 22.4 20.0 48.6 27.9 20.0 47.0 5.1 47.9 0.0 63.0 20.0 37.0 43.0
0.4
80.0 75.8 71 .O
Component A Water. Component B, Methylnaphthalene. Component 6,pcresol. Temperature 36O C. 100.0 0.0 0.0 100.0 0.0 99.1 0.0 0.9 91.0 8.9 98.8 0.0 1.2 80.4 18.8 98.6 0.0 34.6 1.4 63.6 2.0 98.0 0.0 63.4 42.8 97.8 0.0 69.9 2.2 33.9 2.4 74.1 97.8 0.0 15.7 2.7 97.3 0.0 88.4 0.0
3.4 4.8 5.0 6.2 8.4 11.6 11.8 12.7 13.7 15.7 18.0 21.6 24.9 29.0 35.6 38.0 39.7
Smtem 6. Component A, Methanol. Component B, Methylnaphthalene. Component C, Phenol This system wo miscible in all proportiom at 25O C.
System 7. Component A Methanol. Component B, Methylnaphthalene. bomponent C, pCreao1 Thin system wo miscible in all proportiom at 35' C. Component Total A B C D Solvent System 8 Com onent A Water Component B Methanol. Comgonent C, Phdnol. &mponed D, Methylnaphthalene: Temperature 26 C. Conoentrotion of Solvent, 85.7% Methanol 1.0 0.0 0.9 0.1 4.6 6.6 8.9 0.6 17.6 16.1 12.2 2.6 87.2 81.9 16.0 6.8 66.6 47.6 11.6 7.9 67.8 68.0 8.0 9.8 82.4 70.6 2.8 11.8 14.0 88.0 12.8 0.0 78.7
Total Solvent
1.0 3.5 8.0 19.4 27.3 33.2 38.6 44.9 51.2 59.4 68.3 78.8 84.7 96.6
15.8
..
8.6
D
Concentration of Solvent, 73.4% Methanol 99.0 0.7 0.0 2.6 8.6 88.0 79.4 4.4 14.6 14.3 22.0 58.6 20.0 23.5 49.2 24.4 42.4 24.4 28.2 36.0 26.6 33.0 30.1 25.0 87.6 24.0 24.8 18.0 43.8 22.6 48.7 13.2 20.6 14.8 8.6 68.8 62.0 9.5 6.0 70.8 0.0 3.5
0.8 0.9 1.6 6.1 7.8 8.8 10.8 11.9 18.6
..
0.0 0.0 0.0 8.0
C
Syatem 8 (continued)
Symtem 2. Component A Water Component B Methanol. Component C, gbresol. 'Temperature 3d0 C. 0.0 2.7 86.4 97.3 0.0 18.8 82.0 89.0 8.0 3.0 2.6 16.6 11.7 3.3 73.4 88.0 7.8 19.8 18.6 4.0 70.0 82.5 9.2 ao.8 18.7 5.8 80.0 78.0 14.0 26.0 19.4 73.0 7.6 62.1 16.8 81.1 20.1 70.7 9.2 48.0 18.0 84.0 45.1 18.8 86.1 38.8 20.2 48.1 2i:o 14:s &:a 21.8 26.0 6a.7
..
Component
B
0
b
20.0 20.0 20.0
0.0 4.2 9.0
0.0 0.0 0.0
Plane Containing 80.0% Methanol 0.0 38.8 33.3 1.9 32.6 2.4 29.8 4.0 24.7 6.9 18.8 9.7 9.9 18.2 10.7 16.6 16.6 10.7 13.0 11.3 10.4 11.6 11.1 7.3 6.6 9.6 3.3 7.7 3.8 1.6 1.9 1.1 0.3 0.0
Estimted p!ait point. Sample lost in sampling.
100.0 95.8 91.0 83.4 64.8 65.0 66.2 68.4 71.5 71.8 72.7 73.7 76.7 78.0 81.6 84.9 89.0 95.8 98.0 99.7
I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY
1216
Vol. 42, No. 6
TABLEI. EQUILIBRIA AND PRASEBOUNDARY DATA*(Continued) A
B System 9 (Continued)
Component
Total Solvent
D
C
Concentration of Solvents, ,700/, Methanol 1.4 1.0 1.9 2.0 3.4 5.7 6.7 10.6 16.0 17.6 19.7 23.0 24.8 30.0 37.1 45.6 49.8 54.6 62.0 67.7
0.6 0.5 0.8 0.9 1.4 2.4 2.9 4.6 6.8 7.6 9.4 9.9 10.6 12.8 15.9 19.6 21.4 23.4 26.6 29.1
98.0 95.6 91.5 84.0 75.0 65.6 61.3 52.0 45.8 44.4 42.1 39.3 37.4 31.1 22.4 14.1 10.9 7.5 4.6 3.2
2.0 1.5 2.7 2.9 4.8 8.1 9.6 15.2 22.8 25.2 28.8 32.9 35.4 42.8 53.0 65.1 71.2 78.0 88.6 96.8
Phase I Component A B C
Charge Component A B C
Phase I1 Component ___ A B C
p t e m 14. Component A, 70% Methanol, 30% Water. Component B, ethylnaphthalene. Component C, p-Cresol. Temperature loo C. 46:O 44.0 40.0 40.0 35.0 32.0 36.0
50:O 46.0 45.0 40.0 40.0 40.0 34.0
50.0 45.0 45.0 40.0 40.0 40.0 35.0
50.0 50.0 45.0 50.0 45.0 40.0 40.0
4:o 10.0 15.0 20.0 25.0 28.0 30.0
$3
(2.1 4 . 7 89.2 7.6 82.6 15.2 67.5 24.7 50.5 27.7 45.4 Miscible
(?2
6.1 9.8 17.3 24.8 26.9
9'271
80.5
5.1
14.4
66.9 59.0
10.4 14.0
22.7 27.0
2.7 3.0 3,4 5.2 8.7 12.7 17.6
6.9 11.4 14.1 18.2 21.8 25.6
b
b h
Temperature 35O C. 2.4 2.9
97.6 94.0
0.0 3.1
7.8 10.6 15.3 25.6
84.5 77.3 66.4 50.2
7.7 12.1 18.3 24.2
0.0
Quaternary Tie Line Data
Phase I
Component B C 2.7 3.0 7.7 7.0 9.1 12.1 17.3 12.9 19.5 24.9
A 0.3 0.8 1.5 2.4 5.0
A
Charge Component B C
D 94.0 84.5 77.3 67.4 50.6
A
A 27.7 27.7 23.8 23.2 22.8
Phase I1 Component B C 62.4 6.9 57.5 11.4 49.3 18.2 43.7 22.7 36.6 27.0
Phase I Component B C
A
S stem 15. Component A, 60% Methanol, 40% Water dethylnaphthalene. D 3.0 3.4 8.7 10.4 13.6
Phase I1 Component B C
System 10. Component A, 70% Methanol, 30% Water. Component B, Methylnaphthalene. Component C, Phenol. Temperature 25' C.
40.0 35.0 30.0
50.0 40.0 40.0 40.0 40.0 40.0 40.0
0.0 5.0 10.0 15.0 20.0 25.0 30.0
50.0 55.0 60.0 40.0 35.0
50.0 40.0 40.0 40.0 40.0
0.0 5.0 10.0 20.0 25.0
50.0 55.0 50.0 45.0
1.8 2.1 3.6 5.3 9.0 13.3 20.3 (30) (40)
98.2 95.8 91.5 85.7 77.0 66.5 51.5 (38) (27)
0.0 2.1 4.9 9.0 14.0 20.2 28.2 (32) (33)
0.5
99.5 92.0 85.2 76.5 67.3 58.9 49.9
1.7 3.9 7.2 11.0 17.5
0.0 7 .O 13.1 19.6 25.5 30.1 32.6
98.9 90.0 83.0 67.3 57.1
1.1 2.6 2.9 8.1 14.3
0.0 7.4 14.1 24.6 28.6
1.o
Temperature 35' C. 2.4 3.4 4.8 8.8 14.8 (22) (34) (50)
97.6 94.3 90.0 76.5 63.0
0.0 2.3 5.2 14.7 22.2 (28)
50.0 40.0 40.0 40.0 40.0 40.0
0.0 5.0 10.0 15.0 20.0 28.0
3.5 4.0 4.3 4.6 5.0 5.0
96.5 94.0 91.5 89.5 86.8 86.2
0.0 2.0 4.2 5.9 8.2 8.8
99.5 91.1 84.5 74.0 63.8 44.6
0.5 0.7 1.1 3.0 7.5 18.8
0.0 8.2 14.4 23.0 28.7 26.6
S stem 12 Component A 70% Methanol, 30'3' Water. Component B 4i.4% Meihylnaphthalene, '56.6% 2,2,4-Trirnethy?pentane.Component C: Phenol. Temperature 35' C. 40.0 57.5 55.0 50.0 40.0
35.0 30.0
50.0 40.0 40.0 40.0 40.0 40.0 40.0
0.0 2.5 5.0 10.0 20.0 25.0
30.0
2.5 2.5 2.6 2.8 2.9 3.2 3.5
97.5 96.9 96.8 96.0 93.7 92.8 92.0
0.0 0.6 0.6 1.2 3.4 4.0 4.5
99.6 94.9 91.4 83.1 64.5 54.4 45.2
0.4 0.5 0.5 1.3 5.3 8.0 11.2
0.0 4.6 8.1 15.6 30.2 37.6 43.6
S stem 13 Component A 70% Methanol 30% Water. Component B, 69% Metl&4naphthalene, i o % 2,2,4-Trim&hylpentane. Component C,
p-CrRsol. Temperature 35 C.
50.0 55.0 40.0 45.0 40.0 40.0
50.0 40.0 50.0 40.0 40.0 30.0
0.0 5.0 10.0 15.0 20.0 30.0
3.5 3.9 5.5 6.2 9.8 21.6 30.6"
96.5 93.2 88.0 85.0 76.3 56.0 40.0"
0.0 2.9 6.5
8.8 13.9 22.4 29.4"
99.2 91.6 80.7 73.9 65.4 46.0
* All data are in weight perb Sample cent. lost in sampling.
0
Estimated plait point.
50.0 45.0 45.0 45.0 40.0 30.0 20.0
0.0 5.0 10.0 15.0 20.0 30.0 30.0
0.5 3.7 5.5 8.1 15.4 28.8 44.0
99.5 92.1 85.6 77.3 63.6 39.2 24.0
Component B Temperature 35O C'
99.3 92.6 86.9 82.1 78.2 74.8 62.0
0.7 1.2 2.2 3.1 3.8 4.0 10.0
System 16 Component A 70% Methanol 30% Water. Component B, Methyln'aphthalene. Component C, 2-Naphthol. Temperature 35O C. 50.0 51.8 47.4 46.3 42.7 42.9 52.3
50.0 43.5 43.3 39.0 38.3 33.5 20.6
0.0 4.7 9.3 14.7 19.0 23.6 27.1
2 . 4 97.6 7.2 88.0 11.9 77.5 16.4 67.7 21.1 56.0 28.3 44.4 Miscible
0.0 4.8 10.6 15.9 22.9 27.3
98.9 93.3 88.9 85.7 83.4 82.2
1.1
2.1 3.3 3.6 3.7 4.1
0.0 4.6 7.8 10.7 12.9 13.9
S stem 17. Component A 70% Methanol, 30% Water Component B dethylnaphthalene. Comionent C. p-terl-Butylphenol. Temperature 35; C.
50.0 55.3 51.7 52.0 50.0 60.0
50.0 39.8 39.2 33.0 30.0 19.0
0.0 4.9 9.1 15.0 20.0 21.0
2.4 6.8 12.8 21.5 28.1 43.2
97.6 87.8 75.2 59.4 48.5 33.0
0.0 5.4 12.0 19.1 23.4 23.8
98.9 93.1 90.4 85.8 77.2 70.7
1.1 2.4 3.2 3.7 6.8 10.0
0.0 4.5 6.4 10.5 16.0 19.3
System 18. Component A, 70% Methanol, 30% Water. Component B. Hexadeoane. Component C, p-Cresol. Temperature 35' C.
S stem 11. Component A, 70% Methanol, 30% Water. Component B 68'7 Methylnaphthalene, 40% 2,2,4-Trimethylpentane. Component C: Phenol. Temperature 35' C.
50.0 55.0 60.0 45.0 40.0 32.0
60.0 50.0 45.0 40.0 40.0 40.0 50.0
Component C, p-Cresol.
0.8 1.0 3.7 6.1 9.6 21.0
0.0 7.4 15.6 20.0 25.0 33.0
50.0 45.0 40.0 40,O 31.4 25.5 10.1 8.2 5.0 0.0
50.0 45.0 50.0 43.0 29.0 24.0 50.4 53.3 20.0 50.0
0.0 10.0 10.0 17.0 39.4 50.5 39.5 38.5 75.0 50.0
1.4 0.5 0.0 0.2 0.0 0.6 0.2 0.7 0.0
0.0
98.6 98.8 99.4 98.8 98.2 96.8 95.3 93.7 89.0 82.6
0.0 0.7
0.6 1.0 1.8 2.6 4.5 5.6 11.0 17.4
100.0 81.8 80.5 71.0 44.9 31.1 22.8 17.5 5.2 0.0
0.0 0.0
0.0 0.0 0.0 1.8 1.4 4.7 12.0 16.5
System 19. Component A, 80% Methanol, 20% Water. Component B. Hexadeoane. Component C, p-Cresol. Temperature 35' C. 50.0 51.1 30.0 10.7 10.0 2.6 0.0
50.0 30.2 31.4 49.3 40.0 67.2 50.0
0.0 18.7 37.8 40.0 50.0 40.2 50.0
1.5 1.4 0.7 0.9 0.9 0.0 0.0
98.5 97.7 97.4 93.3 92.6 85.7 82.6
0.0 0.9 1.9 5.8 6.5 14.3 17.4
100.0 73.3 44.3 20.4 16.0 5.6 0.0
0.0 0.0 1.6 6.1 7.6 13.0 16.5
System 20. Component A, 70% Methanol, 30% Water. Component B Hexadeoane. Component C. 2-Naphthol. Temperature 35O C. 0.0 50.0 50.0 4.0 56.0 40.0 14.0 46.0 40.0 45.5 30.1 24.5 42.2 29.3 28.5 38.0 30.0 32.0 The liquid-solid legion of Solid 2-naphthol appears
0.0 100.0 0.0 0.0 1.4 98.6 0.4 93.6 0.1 6.2 1.0 98.6 76.3 0 . 1 23.6 0.7 0.8 98.5 1.5 64.8 0 . 1 35.1 0 . 5 98.0 1.8 58.4 1 . 7 39.9 0 . 1 98.1 3.0 52.6 3.4 44.0 0 . 0 97.0 this system was not studied for this work. over the remainder of the system.
(Condudad on page 18f 7)
INDUSTRIAL A N D ENGINEERING CHEMISTRY
lune 19sO
TABLE I. EQUILIBRIA AND PHASE BOUNDARY DATA* (COnClzlded) Charge Component A B C
Phase I Component A B C - A
Phase I1 Component B C
System 21. Component A 70% Methanol 307 Water. Component B, Hexadscane. Componeni C, p-tert-Butyldhenof Temperature 35' C. 50.0 50.0 0.0 1.4 98.6 0 . 0 100.0 00 0 0
!;:
A
tj:;
:::
47.8 43.8 35 6
35.6 16.6 31.6 24.6 27.0 37.4 23 31 45.0 The liquid-solid region of
i:; !::: :;$
:;:: g:: l$:i
74.7 0.4 24.9 63.6 1.7 34.7 48.8 3.7 47 5 o.o 91.0 31.6 ll.l 57 a this system was not studied for this work. 1.0
0.5
0.0
96.8
94.0 91.9
2.2
5.5 8.1
System 22. Component A 70% Methanol 30% Water. Component B, Methylnaphthalene. Component C. Hexahcane. Temperature 35' C. 60.0 50.0 0.0 2.4 97.6 0.0 98.9 1.1 0.0 47.6 48.6 3.9 1.7 90.9 7.4 99.0 1.0 0.0 16.1 69.2 14.7 1.4 81.3 17.3 99.1 0.9 0.0
ii;: i::; 40.9 45.1 49.6
15,7
50.0
o.o
6.8
2.2
44.2 48.1 48.2 50.0
i:: !::! it:; ii:: 8;;
8::
1.4 1.4 1.4 1.4
0.3
0.0
0.1 0.0
0.0
0.0
o.o
o.o
26.2 11.3 4.0
72.4 87.a 94.6 g8.6
99.7 99.9 100.0
System 23. Component A, 90% Methanol, 10% Water. Component B, Methylnaphthalene. Component C, Hexadeoane. Tempersture 3 6 O C. 50.0 50.0 0.0 7.0 93.0 0.0 76.5 23.5 0.0 42.0 66.0 2.0 6.4 89.9 3.7 77.4 23.1 0.8 0.2 81.3 18.6 5.0 84.6 10.5 9.0 81.0 10.0
!:$ :! :!:: t:: ii:! ::$ !89.9 : #: it;: !19.7 40.3 2.5 28.8 68.7 8.1 2.0
40.0 63.6
47.6 41.5
60.0
12.1 5.9 1.5 0.0
35.4 46.6 67.0 50.0
2.5 2.0 2.0 2.0
21.9 9.2 2.5 0.0
75.6 88.8
95.6 98.0
95.2 96.9 99.2 99.5
8.7 1.9 0.1 0.0
1.1 1.2 0.7
The data presented show that solvent compositions near 70% methanol by weight present a satisfactory compromise between solvent power and selectivity for separating tar acids from hydrocarbons. Richer solvents tend to dissolve more of the hydrocarbons and leaner solvents less of the tar acids. Unfortunately, a single solvent of the alcohol-water type does tiot effect the separation of hydrocarbon-free tar acids. To achieve this end i t is necessary to reextract the primary extract with a second solvent of the type represented by the paraffin hydrocarbons. A suitable solvent of this type may be selected togiveaspreadbetween theboilingpoint of the aromatic hydrocarbons extracted and the solvent, sufficient to permit the separation of solvent and hydrocarbon by distillation. An anticipated development is the increased solubility of the less phenolic tar acids in the aromatic hydrocarbon. This may be observed most clearly by comparing systems 10, 14, 16, and 17 at 35" C. (Figures 10, 14, 16, and 17). These systems were similar in all respects except the species of the phenolic component. The paraffinic hydrocarbon systems did not show this same effect (see system 18,19, and 20,Figures 18,19, and 20). Some of the methanol from the solvent preferentially dissolves in the hydrocarbon-rich phaae of all systems. Thus the composition of the solvent remaining in the solvent-rich phase is shifted from the nominal composition in the direction of a higher percentage of water. This change in composition is slight and In all oases was sukh as to increase the efficiency of the separation of taracidsfrom hydrocarbons.
0.1
* All data are in weight per oent.
1217
LITERATURE CITED
(1) Am. SOC.Testing Materials, Standard D 268-48, "Sampling and Testing Lacquer Solvents and Diluenta," Sections 9 through 15.
INTERPRETATION OF THE DATA
The investigation of the ternary and quaternary systems revealed that these systems do not behave in the same manner as the system acetic acid-acetone-chloroform-water used by Brancher et al. (2) in developing their correlation for tie lines in quaternary systems containing one immiscible binary pair. More system have to be studied before it can be whether the correlation suggested in general and these systems form the exception or the correlation is applicable only to the system for which i t was developed.
(2) Brancher, A. V.,Hunter, T. O.,and Nash, A. W., J . Phys. C h m . , 44, 683 (1940). Aww.Chem*i 48# 394 (1935)s (3) Fischeri (4) Kemp, L. C., Hamilton, G. B., and Groaa, H. H., IND. ENG. CRBM.,40, 220 (1948). (5) Postlewaite, J. P., and Bondy, H. F., BZOS-Trip 2153, British Intelligence Objectives Sub-committee, Target C30/472 and C30/4729. (6) Ruderman, 1. W., IND. ENQ.CREM.,ANAL. ED.,18, 753 (1946). (7) Rutzler, J. E., Jr., and Bauman, R. G., Abstractsof Papers, 113th Meeting of AM. CHEM.SOC., Chicago, Ill., pp, 86-0, 87-0, 1948. RmcmxVlD January 14,1950.
Toluene Extraction from Petroleum with Water Solutions G . B, ARNOLD AND c. A, COGHLA" Beacon Laboratories, The Texas Company, Beacon, N . Y
?-
Batch equilibrium data are presented on the recovery of toluene from the toluene concentrate from hydroformed naphtha by liquid-liquid extraction with a water solution of 20% ammonia at 274' and 232" C. and a water solution of 25% ethylene glycol at 302' and 274' C. From these data process calculations are made assuming a threecomponent system of toluene, naphtha, and solvent, and the results are compared with similar calculations on the extraction of toluene with water at 274" and 302" C.
* Present addreas, The Texaa Company, Port Arthur, Tex.
I
T BECAME evident during the early stages of World War I1 that in order to supply toluene for normal deknands and possible needs of the military, considerable expansion of the facilities for the production of toluene was needed. Furthermore, it waa well known that toluene was present in many natural and re formed petroleum stocks. These facts logically led to an investigation of methods of separating toluene from petroleum stocka by a number of procedures, which included liquid-liquid extrac-• tion with selective solvents. A study of the recovery of toluene from a toluene concentrate, prepared from hydroformed naphtha, by liquid-liquid extraction with water at high temperatures has been described (I). This
