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
174
sulted in two liquid phases over most of the solvent composition range. LITERATURE CITED
(1) B r u y n , B. R. de, 2. physik. Chem., 32,63-115 (1900). (2) F l a t t , R., a n d J o r d o n , A., Helv. Chim.Acta, 16, 37-53 (1933). (3) Osborne, N. S.,McKelvy, E. C . , a n d Bearce, H. W., Bull. Bur. Standards, 9, 327-474 (1913). (4) Schiff, H., Ann. Chem., 106, 108-18 (1858); 1 1 8 , 3 6 2 - 7 2 (1861). ( 5 ) Schreinemakers, F. A . H., a n d B a a t , W. C. de, 2. physik. Chem., 67, 551-60 (1909).
Vol. 42, No. 1
(6) Seidell, il., "Solubilities of I n o r g a n i c and M e t a l Organic Compounds," 3rd ed., Vol. I, p p . 1300-02, 1312-14, New Y o r k , D. Van N o s t r a n d Co., 1940. (7) Thompson, A. R., a n d M o l s t a d , M. C., IND.ENG.CHEM?., 37, 1244-8 (1945).
(8) T h o m p s o n , A. R., a n d Vener, R. E . ,I b i d . , 40, 478-81 (1948). (9) Vener, R. E., a n d T h o m p s o n , A . R., I b i d . , 41, 2242-7 (1949). RECEIVED June 28, 1949. Based on a dissertation presented by Raymond E. Vener to the Graduate School, University of Pennsylvania, in partial fulfillment of the requirements for the degree of doctor of philosophy.
erature on active In S. S. KURTZ, JR., SENTA A330N, AND ALBERT SANIIIN, S u n Oil
In order to emphasize the fact that the Eyliman equation has a wide range of usefulness, the authors have summarized available data, including the data of Eyliman, showing that the Eykman equation represents experimental data for the effect of temperature on the density and refractive index of organic compounds quite accurately over a wide range of temperature. PAPER published recently by Dreisbach ( 4 )shows that over the limited range, 20' t o 25" C., the Eykman equation (7, 8)
more accurately represents experimental data for the effect of temperature on the density and refractive index of organic compounds than does the Lorentz-Lorenz equation (3, I S , 14,15)
The conclusions reached by Dreisbach are entirely in accord with the previous conclusions of Kurtz and Lipkin ( l l ) ,Ward and Kurtz ( l 7 ) ,Bauer and Fajans ( d ) , and Gibson and Kincaid (9). The purpose of this paper is t o summarize available data, including the original data of Eykman, showing that the Eykman equation represents experimental data quite accurately over a wide range of temperature. I n Table I Eykman's experimental data for 42 liquid hydrocarbons are compared with values calculated from the Eykman equation, the Lorentz-Lorenz equation, the Gladstone and Dale n-1 equation (IO), - CB, and a simple empirical approximation, ~
An = 0.6Ad, recommended by Ward and Kurtz (27, 18) for correcting the refractive index of hydrocarbons for small changes in temperature. The minimum temperature interval in this table is 31.0" and the maximum, 122.3" C. Table I shows t h a t the observed change in refractive index agrees with the calculated change in refractive index with an average deviation of *3 x per degree if the Eykman equation is used. The simple equation, An = 0.6 Ad, agrees with the data with an average deviation of 1 8 X lo+, and the Gladstone and Dale equation with an average deviation of -26 X while the Lorenta-Lorenz equation shows an average deviation of +38 X 10-8 per degree change in temperature. In the tables of Dreisbach's paper the most reliable data are quoted from the tables of A.P.I. Project 44 ( I ) for seven
Company, Norwood, Pa.
hydrocarbonsTnamely, hexane, heptane, benzene, toluene, ethylbenzene, isopropylbenzene, and styrene. If one calculates the refractive index a t 25" C. from the refractive index a t 20" C. using the constant C1, the average deviation for these 7 compounds between the experimental and calculated refractive index is * 5 X 10-5 for the 5 ' intervals, or =t1 X for a 1O C. temperature change. The average deviation per degree in Table I is, therefore, only one third of the deviations indicated by the limited temperature interval considered by Dreisbach. Table I1 presents hydrocarbon data from the literature other than Eykman data for the effect of temperature on density and refractive index, but considers only data which cover a temperature range of 15" C. or more. (The A.P.I. Project 44 tabulations a t present cover only 5" C. trmperature intervals and are omitted for that reason.) These data do not agree with the Eykman equation as well as do Evkman's original data. The deviations per degree are no worse, however, than are those shown by Dreisbach. The deviations from A n = 0.6Ad are still smaller than those from the Gladstone and Dale and the Lorentz-Lorenz equations; although the diff rrence between equations is much less than it is for Eykman's hydrocarbon data. Table I11 presents corresponding data obtained by Eykman for nonhydrocarbons, This table also shows excellent agreement between experimental d a t a and values calculated from the Ekyman equation. These data are of interest in connection with the theory of refraction, because the regularity of associated liquids in regard t o the Eykman function must mean that association between molecules has little effect on refraction. This is not surprising if one recognizes that refraction in the visible part of , the spectrum for hydrocarbons and other simple organic compounds depends upon the valence electrons (6, 11, l a ) . The frequency of vibration of these electrons is probably not appreciably modified by association effects between molecules. The failure of An = O.6Ad t o represent these data is not surprising as this simple equation was derived for hydrocarbons. Consideration of the currently available data for the change of refractive index and density with temperature leads one to conclude that changes in refractive index calculated by the Eykman equation from experimental data for density a t two or more temperatures are likely to be more accurate than experimentally determined changes in refractive index unless the experimental work is very carefully done. The Eykman equation is entirely empirical; however, it has been shown by Kurtz and Ward ( l b , l 7 ) that the Sellmeier-Drude dispersion equation (6) can be modified by adding one constant SO t h a t i t will give data in quantitative agrecment with the Eykman equation.
115
INDUSTRIAL AND ENGINEERING CHEMISTRY
January 1950
OF TEMPERATURE ON REFRACTIVE INDEX AND COMPARISON OF SEVERAL EQUATIONS WITH EYEMAN'S TABLE I. EFFECT HYDROCARBON DATA"
(All data for the a line of hydrogen) ( Anoalod. Amxptl.) X 104 Lorentz Gladstone and Eykman 0.6 Ad and Dale, Lorenr Anexptl.
-
At =
t2 - tl,
tl,
c.
c.
Compound
PARAFPINS
%
n-Hexane %-Decane n-Heptadecane n-Octadecane n-Nonadecane n-Eicosane n-Heneieosane n-Docosane n-Tricosane n-Dotriacontan e 2 7-Dimethyloctane 5iButylnonane 2-Methylheptadecane 2-Methylnonadecane C2o paraffin Av. for 15 paraffins
14 0 18.5 23.7 35.2 34.6 45.6 49.5 46.7 49.0 80.4 13.1 21.7 15 6 18.1 38.3
31.0 63.8 55.3 46.0 47.3 33.7 31.4 34.2 32.6 59.6 66.5 57.3 63.2 61.4 97.7
..
..
0.0170 0.0292 0.0225 0.0187 0.0188 0.0132 0,0121 0.0132 0.0126 0.0218 0.0306 0.0248 0.0252 0.0242 0.0387
+2 0
+l
-3 -1 0 +1 -1 -1 +l 0 0 -1 0 -2
..
...
+ +0
2 + 5 6
+1
++ ++ 31
+ I 3 1
+ 3 + 4 2 + 3 4
+ +
..
UNBATURATED ALIPHATIC8
2-Octene 1-Hexadecene 5-Butyl-4-nonene 2-Methyl-1-pentadecene 2-Methyl-2-nonadecene 1-Hexadecyne Av. for 6 unsaturated aliphatics
16.3 14.6 18.8 19.7 15.2 17.1
62.5 65.2 60.3 60.0
63.9 61.9
0.0324 0.0270 0.0269 0,0249 0,0255 0,0260
+2 +1 +3 -1 +2 +5
16.9 25.4 19.9 23.0 20 8 19.7
Dicyclohexylmethane Av. for 6 naphthenes
3 3 5 3
0
61.9 55.6 59.3 58.2 58.4 59.8
0.0318 0.0272 0.0267 0.0271 0.0260 0.0242
-3 -3 -1 -2 -3
....
..
Eykman
++ 86 ++147
---
-2 0 +3 -3 -3 +2 0 0 -2 0 -2 *2
-
..
- 16 - 14 - 12
..
..
+ 5
+31 +29 +30 +34 +36 +38 33
-25
+37
0.0293
0
+ 7
- 16
0
+I1
0.0289 0.0325
0 +2
+ 4
- 17
0
4-6 13
13.2
66.4
0.0303
+1
..
....
...
+ 15 ..
+2 +1
..
+
- 32 - 31 - 27 -31 - 32 - 22 - 29
61.7 63.2
..
4-25 +30 4-31 28 4-29 $26 -I-30
++1113 f12 ++3224 +20 +19
63.0
+3
- 23
+ 1-30 +35 ++2625
-
16.6 17 3
- 16 - 17
- 24 - 19 - 23 - 25 - 22 - 24 - 23 - 24 - 23 - 24
+ 4
0
16.8
+ 8
- 28 - 25
$35 +35 +33 4-24 27
+32 ++2434 +33
+ 5 + 8 + 5
CYCLIC OLEFINS
1-Isopropyl-3-methyl- 1-cyclohexene 3-Isopropenyl-l-methyl-l-cyclohexene 2,3,3-Trimethylcyclopentene 2.6.6-Trimethvibiovc10(3.1.1)-2. hexene Av. for 4 cyclic olefins
- 23 -20 - 22
- 26 -21 - 20 - 25 - 20 - 32 24
0 + 5
+3 +8 *4 -5 -5 -2 -3 -5 +2 +4
...
+
?;
- 20 - 17 - 16 - 18 - 19 - 13
+19 +12
+ 2 + 3 10 + 3 + 3 + 5 + 5 + 7 + 3 + 5 + 4
+3 +2
- 15 - 13 - 20
+l
0.6 Ad
C.) X 10' Lorentl; Gladstone and and Dale Loren2
+ 6 +! + 8 +2 + 1; -7
- 7 13 12 13 12 - 8 - 6 - 8 - 8 - 13 16 13 - 15 14 23
..
.. NAPHTHENES
Methvlcvclohexane
0
+ + + +
(Deviation,"
+ +23 + 13
- 28
0 6 3 8 3 10 + 8
- 23 - 22 -29 -34 - 24 29 30 35 29 25 25 28 -26
-25
- 26
-26
+37
E
+
++4043 +39 +38
AROMATICS
Benzyltolueneb 14.7 21.4 n-Propylbenzene tert-Butyltoluene b 19.8 15.1 Cymeneb 20.3 Pentaethylbeneene 18.3 Hydrindene 15.3 Indene 15.4 1 2 3 4-Tetrahydronaphthalene 15.2 1:2:3:4-Tetrahydroaoenaphthene 17 3 Cyolohexylbeneene 11.0 Diphenylmethane Av. for 11 aromatics .. .. Av. for 42 liquid hydrocarbons a All experimental data from Eykman (7).
122.3 67.5 58.7 61.9 87.6 58.0 63.6 62.6 65.1 62.9 120.1
.. b
0.0555 0.0340 0.0284 0.0308 0.0379 0.0292 0.0330 0.0294 0.0290 0.0276 0.0568
0
+7
+5
0
-3
- 5 - 3
+2 +2 -3 -1
+ 6
0
tl -I-6
... ...
....
....
++ E5 + 7 - 1
.. *.
- 28 - 15 - 17 - 21
+6 +7
+ -
0
-5
0
-21 17 - 19 - 22 - 19 - 16 - 30
-
+
+3 +3 -5 -2 +2
0 4-8 fll
+5'
..
- 1 * 5
d=3
..
*3
* 8
'
Compound n-Pentane n-Octane n-Undecane n-Dodecanea 16-Methylhentriacontane 16-Ethylhentriacontane 16-Butylhentriacontane Propene 2-Methyl-2-butenea 1-Hexene Propyne 1-Hexyne 1-Heptyne Cyclopropane I-or-Pineneb Benzene Av. for 14 liquid hydrocarbons a Omitted from average.
tl, '
c.
.... b
--
At t2 O
tl,
c.
..
-
++ + +
Isomer not stated in original reference.
ON REFRACTIVE INDEX AND COMPARISON OF SEVERAL EQUATIONS TABLE11. EFFECTOF TEMPERATURE DATAFROM LITERATURE
4
---
+59 +55 +44 +40 +46 59 68 +46 54 +46 +61 53 +38
(All data for D line of sodium) (Anoalod. Anexptl.) X 104 Lorentz Gladstone and Eykman '0.6 Ad and Dale Lorenr -6 13 +3 +7 +7 +1 +6 16 +8 +2; +22
-
Anexptl. 0.0279 0,0119 0.0112 0.0111 0.0122 0.0179 0.0194 0.0232 0.0158 0.0169 0.0117 0.0159 0.0126 0.0298 0.0173 0.0136
....
+-
-
0
5,"
- 19 0
++6-317
+3 +4 16 24 -3
-
t-1: +
-5
$29 13 -3
..
..
2 2,6,6-trimethylbicyclo[3.l.l]-2-heptene.
-
t- ;10:
0.6 Ad
-
..
Lorentz Gladstone and and Dale Lorenr
. ~ n
+- 15 13
0 -4 10
..
Eykman
n
-9
-4 13 -- 10
HYDROCARBON
(Deviation/o C.) X 10'
0 +-50+618 -3; -76a -9Ga
-9
- 17 -26
WITH
-in
+-3612 +;,"
-4 +61 +34 - 15
t15
*24
-21 -8 -53 -104a
-m -- 24 - 43 - 40 0 - 11
Reference
-c4r
+34 4-53 4-37
+,3!"
- 50
+60 +20 +24 76 58 35
*28
+47
(16)
(6)
$4
I/?)
++ +
* "
INDUSTRIAL AND ENGINEERING CHEMISTRY
176
TABLE111. EFFECT O F TEMPERATURE O K REFRACTIVE INDEX A S D COMPARISON
OF
SEVERAL
Vol. 42, No. 1
EQU.4TIONS WITH E Y K X W ’ S
NOSHYDROCSRBOK DATA“ (All data for the
01
line of hydrogen)
-
(Anoaled.
At = tl,
c.
Compound
tl
”
-
tl,
C.
Ancxl,tl.
Eykman
0.6 4 d
X 10d Lorentz Gladstone and and Dale Lorena
Anexptl.)
(Deviationlo C.) X 106 Lorenta Gladstone and Eykinan 0.6 Ad and Dalc Lorona
SATL-RATED A L C O I I O L 8
2-~Ietlisl-2-l)ritanol 1-Heptanol 1-Octanol 5-Nonanol 5-Butyl-5-nonanol 4-Propyl-4-deoanol 2-~~ethyl-2-tridecarlol 2-Met hyl-2-pcntadecanol 3-Ethyl-3-tetradecanol 3-Ethyl-3-hexadecanol Av. for 10 saturated alcohols
13.0 18.7 18.4 16 22.7
15.6 16.6 25.2
15.3 22.8
..
66 61.2 61.4 63.4
56.0 63.6 65.2 55.6 65.6 56.6 I
.
0.0343 0.0240 0.0242 0.0272 0.0264 0.0282 0.0275 0,0231 0,0290 0.0241
....
+47
-1
+; $; 0 4-24
-19
z;; -16
+I
f20
-14
-1.5
+2 4-2 -1
+21 +18 +15 +20 +13
..
..
+A
-15 -12 -15 -15
..
+20
;::
4-10 +21 +23
-2
+3
0 0 +2
+Z
+21
0
+20 +24 4-18
+4 4-3
..
4-71 +44 +36 +38
+36 4-33
-2U
-18 -21 -25 -25
-24 -23
+28 +27
-22
-2
4-23
-26
1 2
+37
-24
+142 +l5l 4-146
-10 -11 -10 -15
-8‘1
-20 -15
+30
-23
+30 +39 +29 f30 f38 +36 +32 +36
+37
+32 +34
S A T U R A T E D A C I D S A S D ESTERS
Pentanoic acid Trimethylacetic acid 3-Methylbutyric acid 4-Xethylpentanoic acid 2-Pro~vloentanoicacid
18.2 36.5 13.6
21.5 15.1
19.7 12 2
45.2
Propyl stearate h v . for 11 saturated acids and esters
61.4 46.5 64.2 59.7 66.6 60.4
66.2 33.6
0,0247 0.0197 0.0267
0,0236 0.0264 0,0260
0.0288
60.6
44.6
..
0.0126 0.0245 0.0236 0.0167
..
,...
16.8
61.1 44.0
0.0251 0,0169
18.9 19.1 35 G
60.6
+7
+87
++9470
+6 +8
+4
+68 +57 54 61 22 36 +26 +20
+1
++ +
+5 0 +Z +Z +1
+
+4
..
..
-6 --J
-7 -9 - 13
- !i - 16 -.5 - 12 - 12
-0
+24
+- 2518
+20 +20 123
+4- 2012
+20 19 +17
+
+11 +13 +I2 +6
+2 -9
+114 +86
0
t 7 8
+G +3
f 0 7 A50
T 2
+43
0 -3 -2
+123
+8 +7
+46 ”93
-23
-10 -10 +20 -14 -16
$39 +30 +30 +33 $30 +38 +30 +35 4-33 +32 +38 +36
U S S A T U R A T E D ACIDS
4-Pentenoio acid 10-Undccenoic acid Av. for 2 unsaturated acids 1-~lethoxy-Z-iso~~ropyl-5-metl1yl-
benzene
34.6
..
1,2-Dibydroxy-4-propylbenaene
..
,...
-14 -11
“18
$-12
..
+55 f8‘3
-24
420 +27 -28
-23 -23
P H E E O L S A S D DEKIVA’TII‘ES
16.0
63.0
0,0299
+3
+I8
-16
+32
+4
+29
-25
+5l
16.7 17.9
62.6 62.5
0,0280 0.0252
+4 +5
+14 +41
-14
-11
+30 +34
....
, .
+G +8 +6
122 +G5 +39
-22 -18 -22
+49 +55 +52
-18 -13
+65 +SI
+12 +42
-29 -34 -24
+59 +69
l-Ethoxy-2,4-diisopropyl-5-iiictbyl-
benzene
175 +24
0 -2
..
.Iv. for 3 phenols and derivatives Ethyl 2-(3,4-hlethylenedioxyphenyl)acetate 17.3 AIethyl-5-phenyl-2,4-pentadienoate 1 9 . 8 Ethyl 5-(3,4-methylenedioxyphenyl)2,4-pentadienoate 7.0 Propyl 2,3-diphenyl-2-propenoate 16.2 .4r. for 4 aromatic esters ..
..
AROblATIC ESTER8
60.7 57.6
0.02G1 0.0240
+10
+87 0
-11 -7
+34
73.2 64.1
0.0347 0.0309
+3 -2
+8
-22 -22
+60
..
..
-7
+39 +43
+17
-65
-10
-12 -33
+66 +66
+I2
+78
-15
$60
-6
+11
+72 =t56
-16
*61
-20
t48 +60 +43
....
1 6
+7
..
..
$144
0
+47
+ll
+38
+82
AROZIATIC K E T O X E B
1-Phenyl-2-propanone I-Phonyl-3-propen-2-one 1-4cetyl-2-ethoxy-4-mothoxy-3metliylbenzene
20.1 14.8
59.0 64.9
0.0269 0,0323
18.9
50.6
benzene 16.6 Av. for 4 aromatic ketones .. Av. for 34 liquid nonhydrocarbons .. a A11 experimental data from Eykinan ( 7 ) .
79.0
I ,5-Diacctyl-3-methyl-2,4-digropouy-
-40 0
+38 -7
-22
0.0253
+7
+47
-9
+36
0.0246
+la
+57
-4
+38
..
..
..
..
I t has also been shown that the Eykman equation represents rather accurate data for the effect of pressure on the relation between density and refractive index ( 7 , 9, l a ) . The point which the authors wish to emphasize is that the Eykman equation has a wide range of usefulness and should be more widely known and used in the future than it has been in the past. LITERATURE CITED
(1) Am. Petroleum I n s t . , Research Project 44 a t N a t l . B u r . S t a n d ards, “Selected Talues of Properties of Hydrocarbons,” as of Dec. 30, 1948. (2) B a u e r , N., a n d F a j a n s , K., “Physical M e t h o d s of Organic C h e m i s t r y , ” Vol. I , p. 667, New Y o r k , Interscience Publishers Inc., 1945.. (3) Debye, P.,“ P o l a r i\.lolecules,” New York, Chemical Catalog 1929. (4) Dreisbach, R. R., IXD.E N G .CHEM.,40, 2269 (1948). (5) D r u d e , P., Ann. Physik, 14, 677 (1904). (6) Egloff, G., “Physical Properties of Hydrocarbons,” Vol. I, New York, Reinhold Publishing Corp., 1939: I b i d . , T‘ol. 11, 1940; Ibid.. Vol. 111, 1946; Ibid., Vol. I V , 1947.
co.,
0
+ 15 =to
(7) E y k m a n , J. F., in “ K a t u u r Verhandellng Hollandsche M a a t s c h a p p i j der W e t t e n s c h a p p e n , ” edited by A. F. Hollem a n , Series 3, Vol. 8, 1919. ( 8 ) E y k m a n , J. F., Rec. trap. chim.,14, 185 (1895). (9) Gibson, R. E., a n d Kincaid, J. F., J. Am. Chem. Soc., 60, 511 (1938). ,(lo) Gladstone, J. H . , a n d Dale, T. P., Trans. K o g . Soc. ( L o n d o n ) , 153, 317 (1864). (11) K u r t s , S . S., J r . , a n d L i p k i n , M . It., J . Am. Chem. Soc., 63, 2158 (1941). (12) K u r t z . S. S.. Jr.. a n d TVaid, A . L., J . FrankZCn Inst., 224, 583, 697 (1937). (13) L o r e n t s , H . .4.,“Theoiy of Electrons,” Leipaig, B. G . T e u b n e r , 1 snq
(14) Lo&;&, H . A , , W i e d . Ann., 9, 641 (1880). (15) Lorens, L. V., Ibid., 11, 70 (1880). (16) S u i d a , H . , a n d P l a n c k h , I%.,Ber., 66,1445 (1933). ENG.CHEM.,ANAL.ED., (17) Ward, A. L., a n d Kurta, S . S., J r . , IND. 10, 573 (1938). (18) W a r d , ii. L., K u r t s , S.S., J r . , a n d Fulweiler, W.H . , “Science of P e t r o l e u m , ” edited by D u n s t a n , A . E., N a s h , A. W., Brooks, B. I.. a n d Tizard. H. T.. Vol. 11, DD. . 1146-7, London, Oxford University Press, 1938. RECEIVED September 20, 1949.
