INDUSTRIAL AND ENGINEERING CHEMISTRY
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Vol. 47, No. 8
temperatures in degrees Fahrenheit are available on request from
( 2 ) Dreisbach, R. R., “Pressure-Volume-Temperature Relationships
the authors.
Sandusky, Ohio, 1952. (3) Myers, H. S..and Fenske, 11. R.. IND. ENG.CHEM., 47, 1652 (1955). (4) Stull, D. R.. I b t d . 39, 517 -50 (1947).
LITERATURE CITED
(1) Am. Petroleum Institute, A P I Research Project 44, Satl. Bur. Standards, November 1947.
of Organic Compounds,” 3rd ed., Handbook Publishers,
RECEIVED for review J u l y 21, 1953.
ACCEPTEDFebruary 23, 1955.
Properties of High Molecular Weight Hvdrocarbons R . W. SCHIESSLER AND F. C. WHITMORE’ Department of Chemistry, T h e Pennsylvania State University, University Park, Pa.
I
NTERPRETATION of the effect of molecular constitution on the physical properties of pure substances has contributed greatly t o man’s understanding of t h e phygical world, and has often permitted the segregation and evaluation of intra- and intermolecular effects. Because of the variety of molecular structures possible, compounds of carbon have been especially useful in such investigations, and the compounds of carbon and hydrogen are usually taken as reference structures to which other carbon compounds are related. For these and other cogent reasons, 1
Deceased J u n e 24, 1947.
correlations of molecular architecture with physical properties and interpretations for hydrocarbons occupy a unique position in the field of molecular physical chemistry. Because of the great number and variety of possible structures, hydrocarbons containing many carbons per molecule ( C12 to Cm) are especially attractive for the investigation of relations of molecular structure and physical property. A t these higher levels of molecular weight, small, progressive changes in chemical architecture are possible, thus permitting determination of the effect of stepwise cyclization, stepwise chain branching, or other changes. However. increased difficulties in synthesis and purifi-
August 1955
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
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As the molecular weight level of the hydrocarbons to be precation a t the higher molecular weight levels have prevented pared increases, availability of suitable intermediates becomes a extensive study of higher hydrocarbons until recent years. serious factor in the consideration of synthetic routes. I n the Schiessler and McLaughlin (69) have reviewed the synthesis and Cpj to C,o region, the problem of synthesis intermediates becomes purification problems and offered some solutions. Other benefits very troublesome indeed. Often the practical synthetic method of studies of physical properties of pure higher hydrocarbons are involves a difficultly prepared starting material, and the major their usefulness in the prediction of properties of unknown effort in the hydrocarbon preparation frequently was devoted to hydrocarbons, their contribution to our understanding of the the synthesis of such an intermediate chemical. liquid state, their improvexent of our understanding of the high The selected synthetic scheme usually has been run first on a boiling fractions of petroleum, and their utility in the developrelatively small scale in a pilot experiment. Often the reactions ment of advanced analytical techniques for determining the comwere being performed on relatively unknown materials for the position of high boiling petroleum fractions. first time. Possible total loss of a laboriously prepared interStudy of the synthesis and properties of pure higher hymediate, and possible undrocarbons n as pioneered expected problems of purifib y H u g e 1 (10). S u i d a cation, are best met by such and Planchk ( 5 7 ) , Landa, a trial experiment, the Cech, a n d Sliva ( 1 4 ) , The results reported in this paper represent the comadditional labors involved W i b a u t , O v e r h o f f , and bined efforts of the authors and the following other frequently being well reJonker (41), Neyman-Pilat chemists: J. A. Dixon, J. N. Cosbp, W. P. Acton, warded. and Pilat (ZO), and Larsen, D. G. Clarke, W. IC. Conn, K. C. East, N. R. Eldred, Purity of Starting MateThorpe, and Armfield ( 15 ) F. B. Fischl, David Flitter, E. .T. Goldberg, C. H. Heri, rials and Synthesis Interhave published data on J. F. Hosler, G. T. ICerr, H. H. ICuehner, R . L. Mem e d i a t e s . Overemphasis properties of several higher Laughlin, P. C. Miller, G. W. Pearce, C. s. Rowland, of the importance of great hydrocarbons. Of the early A. W. Kytina, W. S. Sloatman, R. M. Speck, L. 13. care in purifying etarting work, the most significant Sutherland, and C. A. Weisel. materials and intermediates and extensive is that of would be difficalt. AdeMikeslra and others (18,19), quate purification of the who synthesized 52 hydrofinal hydrocarbon may be carbons in the CIO to Cso nearly impossible unless intermediates are free from komeric, range having a variety of structures, and determined many of homologous, or closely similar impurities. Time devoted t o the their properties. Schmidt and others (33, S 4 ) studied series of npurification of starting materials and intermediates is very a orth paraffins and n-alkyl derivatives of benzene, cyclohexane, and while; effective purifications usually can be accomplished rather cyclopentane. Smith and others (36) reported several alkglnaphreadily a t the lower molecular weight level of these substances. thalenes and their hydrogenated analogs. Doolittle and Peterson After each step in the purification of an intermediate, ( 3 ) prepared and studied a number of n-paraffins. Wise and appropriate physical property and spectral data were studied associates (6, 7, 12, I S , 16, 17, 55) have reported over 100 pure to establish purity and uniformity of composition. Spectral hydrocarbons, mainly dicyclics in the C12 and CISrange. data have been especially useful for elucidating the nature and A research group directed by R. W. Schiessler and the late F. C. estimating the quantity of impurities present, frequently pointing Whitinore has prepared ( S I , 52, 38-40) over 230 pure hydrocarthe way to worth-while additional methods of purification. bons, rovering many molecular types and c!asses over the range Synthetic Methods. The methods of preparing the hydrocarCs to (360, with t h e greatest concentration in the C Zto~ C3o region. bons in Table I (and in the more detailed table available from This paper records the physical properties of the pure hydrothe Photoduplication Service, Library of Congress), are being carbons studied b y this group. Subsequent publications will reported in the appropriate journals (31, 52, 38-40). The correlate these physical properties with hydrocarbon structure, hydrocarbons were chosen to establish the effects on physical and will report viscosities and densities at high pressure. properties of rertain features of molecular structure-for example, METHODS O F SYNTHESIS AND PURIFICATION homologous series t o establish the contribution of repetitive -CHz-groups, cyclization series to determine the effect of proFor the study of the relation of molecular structure to physical properties, high purity is essential. Special problems are inherent gressive cyclization to a certain type of ring structure, and symmetry series in which the relations among alkyl, aromatic, in the preparation of pure hydrocarbons of high molecular and analogous cycloparaffinic structures would be elucidated. weight. T h e most important problem is the large number of The most useful and versatile methods for preparing pure possible isomeric or homologous impurities having relatively higher hydrocarbons employ the Grignard reaction, involving slight differences in physical properties, such as vapor pressure, chemical combination of organomagnesium halides M ith a variety which minimize the power of fractional separation processes for purification (40). The very low vapor pressures a t high molecof reactants. Of special interest for preparation of higher h j drocarbons are the reactions of organometallic halides with esters, ular weight further complicate the situation, because the high pressure drop of most high-efficiency fractional distillation colaldehydes, ketones, nitriles, allylic halides, and acid chlorides. umns usually precludes their use a t very low operating pressures. Many of the hydrocarbons reported were prepared by application of a Grignard method, frequently involving an intermediate Judicious selection and careful study of the synthetic methods tertiary alcohol from reaction of a Grignard reagent with a ketherefore have been essential. The methods chosen must be tone or ester, and dehydration of the tertiary alcohol to an olefin free of concomitant reactions yielding by-products difficult to which was then hydrogenated catalytically t o the desired hyseparate from the desired product by available purification techniques. Reaction sequence and order of introduction of difdrocarbon (51, 32, 38, 39). Other hydrocarbons were syntheferent groupings often were important. Choice of method also sized b y condensing a Grignard reagent with the appropriate has been governed by applicability to large bench scale operation, nitrile, forming a ketone which then was reacted with a second as approximately 200 grams of final pure hydrocarbon is desired Grignard reagent, producing tertiary alcohol which yielded for extensive study of physical properties. By aiming for a a branched hydrocarbon on dehydration and hydrogenation minimum of 400 grams of product, an adequate number of (40). I n other cases, the ketone obtained by the Grignardfractions was secured from the various purification steps to pernitrile reaction was reduced directly t o the corresponding hydrocarbon by a modification of the Wolff-Kishner method (68, $6). mit selection of the purest material.
INDUSTRIAL AND ENGINEERING CHEMISTRY
1662
Table I.
P0U No. Structure
Empirical formula Theor. mol. wt. Abs. vis., cp. 32O F. 68' F.
looo F.
140' F. 210' F. Kin. vis., cs. 300' F. 400' F. 450° F. Antoine constants' for c p . 32O to 210' F. A
E b
Kin. vis.! index VTRO Aniline pt., C. Furfural pt., C. Density i 32' F. 68' F. 100" F. 140' F. 2100 F. Melting pt., C. Boiling pt., C. 0.50 m m . 1 . 0 0 mm. 2.00 1nm. 5 . 0 0 mrn. 10 00 mm. Heat of vap., cal./g.k nn, exptl.
200 C.
Representative Hydrocarbons and Their Propertiesa
5,14-Di-nbutyloctadecane 55
n-Eicosane 540 n-CZQ
c&-c-c8-c-c4
ClOH42 282.5
CnsHar 366.7 b
b
19.72 9.678 4.92 2.14
b
4.290 2.664 1.424 1.1372 0.7353 0,6124
1.446 0.8748 0.7160
1.292493 355.1490 126.462 174 -0.9538 106.1 138.1
1,222354 319.7048 166.175 119 -1,320 111.3 145.7
0,8021j 0.7888i 0.7769 0,7621 0.7361 36.6
0.82081' 0.8077 0.7970 0.7816 0.7558 5.7 172.0 185.0 199.5 219.0 235,O 58
137.0 149,5 162.5 181.0 196.5 69
1 ,4508
1.44243 1.4385C 1.4346
9(2-Phenylethy1)heptadecane 87
ca-c-ca
1,7-DicyclopentyI4 (3-cyclopentylpropy1)heptane 113
[
] - *c- , i
f:
Cz6Hu 344.6
1-a-Naphthylpentadecane 174 0
-
C
I
S
CesHza 338.6
37.70 14.84 7.90 4.34 2.02
178.5 51.41 22.46 10.13 3.87
b
6
17.56C 8.384 2,882 d d
d
1,198406 324.8565 156.095 139 - 1.191 53.1 85.2
0.8699 0.8560 0.8441 0.8296 0.8040 -26.7
1.251845 382.9741 163.780 116 -_-
-1,557 88.6 135.5 0.9020 0.8887 0.8774 0.8635 0.8379 -23.7
175.5 189.0 203.5 223.5 240.0 62
184.0 198.0 213.5 234.0 251.5 61
1.4806 1.4767 1 ,4729
1.4829 1,4791 1.4754
1.4469 30' C. 1.4430 40' C. Mol. refraction 122.0 114.3 94.8 Found 122.3 94.6 114.0 Theor.1 0.3333 0.3323 0.3357 Spec. refraction Mol. voluniem 454.1 402.7 388.1 Found 454,5 ...... 356.8 Calcd. ( 1 1 ) For properties of additional hydrocarbons, refer t o note a t end of paper. b Melting oint too high. C SupercooTed sample. d Not yet determined. B __ - A with 1 in ' K. and n in cp. e Antoine equation form: log n
-
Vol. 47, No. 8
3,253243 1300.324 21.854 119 - 1.452 h
0.9275i 0 , 9 1 4 5I 0.9029 C 0.8885 0.8631 41.8 201.5 215.0 230.0 250.5 267.0 69 Solid Solid 1.5215C
9 [ a cis 0 3 3 Bloyoio-~ciyi)methyllheptadecane 178 Ce-c-cs
CZBHSO 362.7 109.3 34.68 15.92 7.546 2.993 1.751 1.027 0,8245 1.332492 385.5112 158.864 109 -1.476 100.1 140.1 0,8705 0.8577 0.8461 0.8320 0.8069 d
182.5 196.0 210.0 229.5 245.0 62 1.4705 1.4668 1.4631
111.4 111.1 0,3213
114.5 110.9 0.3381
118.1 117.9 0.3256
390.1 391.3
370,3
422.8 422.5
......
t - c
k?krage percentage deerease in visoosjty per F. between 100' and 210' F. (dB1 h Hydrocarbon crystallized before solution temperature was reached. i Corrected for air buoyancy, grams per ml. j Extrapolated value. k Calculated from 0.5 and 10 mm. boiling points using Clausius-Clapeyron relation. 1 Calculated using 2.420 for atomic value of carbon. m A t 20° C.
Since with few exceptions the hydrocarbons reported have been first synthesized by the authors, the Grignard synthetic route is especially appropriate because it has been investigated so extemively that many of its limitations are known ( 1). Even with the Grignard methods, careful research often is necessary, as unexpected and new reaction routes are still being found (2424). Many other organic reactions have been used in synthesizing hydrocarbons or their intermediates (SO), including the condcnsntion of acid chlorides with the appropriate aromatic hydrocarbon in the presence of aluminum chloride, and conversion of the ketones thus obtained t o hydrocarbons by the methods indicated above. The Friedel-Crafts method of condensing aromatics with alkyl halides has been avoided because of the possible complicating isomerization of the alkyl group. Extensive use has been made of high pressure hydrogenation. Most of the aromatic hydrocarbons were prepared by
selective hydrogenation of aromatic olefins using copper chromite or Raney nickel catalysts. Xearly all of the cycloparaffinic hydrocarbons containing six-membered rings were produced by hydrogenation of the analogous aromatic compound over Raney nickel or kieselguhr-supported nickel a t high pressure In all cases, the positions of side chains or branches in the hydrocarbons have been established. Great care has been taken to assure the identity of the hydrocarbons reported. Wherever doubt existed, both the reaction course and the products have been investigated t o establish the structure of the intermediates and the final hydrocarbons. With few exceptions, however, no attempt has been made t o separate the geometric isomers, often numerous, known to be formed by hydrogenation to the corresponding cycloparaffins of fused-ring aromatics or polyalkyl aromatics. I n all cases, the aromatic hydrocarbons which were hydrogenated were of high
August 1955
INDUSTRIAL AND ENGINEERING CHEMISTRY
purity, so that the positional structures of the cycloparaffins are well established. Considering t h e effort required t o determine the geometric structure of the steroidal hydrocarbons such as cholestane, the impracticality of such determination obviously places it beyond the scope of this work in most instances. Even if the cis-trans isomers could be separated efficiently, it would be very difficult t o determine their exact geometric structure. Therefore it must be recognized that most of the fused-ring cycloparaffins and polyalkyl cycloparaffins reported here are the mixtures of cis-trans isomers produced by hydrogenation of the corresponding aromatic analogs over nickel catalysts a t about 200" C. and a pressure of 1500 pounds per square inch. Many of these hydrocarbons have been prepared a second time by the same method; the good agreement obtained between physical properties of the separate preparations indicates the ability of the synthetic method and hydrogenation technique t o reproduce the mixture of cis-trans isomers obtained, Purification Methods. Except where precluded by thermal instability or high melting point, intermediates were purified by careful fractional distillation through 40-plate-glass-helix-packed columns, and only the constant-boiling fractions of constant refractive index were retained for synthesis use. Solid intermediates were recrystallized t o constant melting point. Whenever suggested by known or likely impurities, chemical treatment and chromatographic adsorption were used for their selective removal, The newer techniques of urea and thiourea complexing have been employed in recent purifications ( 2 7 ) . With very few exceptions, intermediates of high molecular weight and final hydrocarbons were purified b y fractional distillation a t 0.5 t o 1.0 mm. through a special high vacuum column which is a modification of a design by Fenske (4). Of the constant-boiling fractions of constant-refractive index, only those fractions constituting a viscosity plateau constant within =t0.3% ( 2 6 ) were retained for determination of purity and of physical properties. For some hydrocarbons melting above room temperature, fractional recrystallization was a useful purification technique. I n all preparations, chromatographic adsorption with silica gel or activated alumina was employed t o remove traces of polar impurities. With t h e exception of the 1-olefins, excluded because of possible isomerization, all hydrocarbons were given a final passage over a column of silica gel immediately prior t o ampouling under pure nitrogen. Many of the intermediates and final hydrocarbons have been examined by ultraviolet, infrared, and mass spectra ( 2 1 ) techniques, both to record the spectra and for an additional check on purity. Purification methods have been more thoroughly discussed by two of the authors (29). Unquestionably a detailed knowledge of the chemistry of the synthesis reactions is the most important single factor in preparing pure chemicals. Such knowledge permits selection of the best combination of purification methods to produce a hydrocarbon of high purity, in which probable trace contaminants will be so similar in molecular structure t h a t they will have virtually no effect on most physical properties. This is the major guiding principle, regarding purity, under which the hydrocarbons reported here were prepared. Criteria of Purity and Uniformity of Composition, Since high purity is imperative for this work, a purity of 95 mole yo was established as the minimum acceptable level. Reliable estimations of the purities of hydrocarbons are of great importance and are often difficult. The calorimetric freezing curve method of estimating purity ( 5 )is impractical for most of these higher hydrocarbons because it presupposes a rather rapid rate of Crystallization, usually unattainable with viscous hydrocarbons of high molecular weight. For this and other reasons, the melting-curve calorimetric tech-
1663
nique was adopted; it has the added advantage that heat of fusion is determined experimentally at the same time as melting point and purity, as well a9 heats and temperatures of solidsolid transitions occurring near the melting point. The constantheat conduction melting point calorimeter developed for this purpose, capable of yielding melting points t o f 0 . 1 " C., heats of fusion to i50J0, and purities to 1 0 . 1 mole yo,will be described in a separate publication (26). Though useful, solid-liquid transition methods for estimating purity are not considered final because they presume ideal mixtures in the Raoult's law sense, with the formation of eutectic, whereas solid solutions form frequently when mixture components are similar in molecular structure, and other possible difficulties must be considered (26). When the exact nature and behavio1 in mixtures of the impurities are unknown, interpretation of solidliquid transition data cannot be considered as conclusive evidence of purity. Much emphasis has been placed on the chemical history of a hydrocarbon in estimating its purity. Each synthesis stage was followed by a careful purification to minimize contamination of the final hydrocarbon by by-products. Refractive index t o &0.0001 was determined on all constant-boiling fractions from fractional distillations. Viscosities to =tO.l% were then determined for the fractions of constant refractive index, as viscosity is much more sensitive to variations in composition than is four-decimal place refractive index (26) and is sometimes as sensitive as calorimetric melting point determined to &0.lo C. Only fractions having viscosities within 1 0 . 3 % of the average of the viscosity plateau were retained for further study, Following examination by high mass spectra ( S I ) , and by infrared and/or ultraviolet where the chemical history indicates utility of these physical methods, final hydrocarbons which successfully pass inspection were crystallized, if possible, and their purity was estimated by the calorimetric melting curve technique. Fused cycloparaffins and polyalkyl cycloparaffins, consisting of mixtures of cis-trans isomers, were prepared by total hydrogenation of the analogous aromatic hydrocarbons of high purity. PHYSICAL CONSTANTS
The physical properties of the hydrocarbons reported are the experimentally determined values, or were computed from experimentally determined values. -4lthough the data have been checked for internal consistency by graphical techniques, no smoothing methods have been employed. For those hydrocarbons with high melting points, some properties were determined a t temperatures other than those adopted as standard for this investigation. Table I lists data for representative hydrocarbons classed as n-paraffins, branched paraffins, nonfused aromatics, nonfused cycloparaffins, fused ring aromatics, and fused ring cycloparaffins. VISCOSITY.Kinematic viscosities were determined a t 32" to 210" F. with Cannon-Fenske ( 2 )viscometers by ASTM D 445-39 Method B in baths constant to &0.05O F. Kinematic viscosities a t 300" to 450" F. were determined in Ostwald viscometers in constant temperature vapor baths (8). Absolute viscosities were calculated from the isothermal kinematic viscosities and densities. Viscosities were determined with a reproducibility within f 0.2y0,. All viscosities are referred to the new standard viscosity for water a t 20" C., 1.0038 centistokes. Investigation by one of the authors ( 2 3 ) has shown the empirical Antoine equation capable of reproducing the data on absolute viscosity a t 32' to 210" F. to &0.3y0on the average. The very rapid change of viscosity with temperature makes graphical interpolation inaccurate, and the precision of fit of the Antoine equation recommends it as a useful interpolation formula, Therefore the Antoine equation constants for absolute viscosity between 32" and 210" F., as determined by least squares fitting t o the experimental viscosity data, have been included in the table.
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INDUSTRIAL AND ENGINEERING CHEMISTRY
DENSITY.The densities were measured a t 32” to 210” F. in baths held constant to ~k0.05” F., using 5-ml. pycnometers which had been calibrated with pure water. All recorded values have been corrected for air buoyancy, and were determined with a precision within fO.OOO1 gram per ml. The accuracy of the densities is estimated as within 3=0.0002 gram per ml. VISCOSITY-TEMPERATURE BEHAVIOR.The effect O f temperature change from 100” to 210” F. on the viscosity of hydrocarbons is represented by both the kinematic viscosity index and the viscosity-temperature rating (VTR). Viscosity index (9) is included because of wide usage by petroleum chemists. However, its drawbacks are serious, especially when the index is below 0 or above 100 (26). The viscosity-temperature rating is the mathematically average decrease in viscosity between 100 and 210” F. expressed in per cent per degree Fahrenheit, arrived at by integrating between the temperature limits chosen (62). ANILISE POINT.Solution temperatures in aniline of an equivolume mixture of aniline and the hydrocarbon were determined by ASTM Method D 611-41T with a reproducibility within h 0 . 2 ” C. 4 2-ml. sample of both aniline and the hydrocarbon was employed, and an infrared lamp was used as a heat source in the determination.
FURFURAL POINT. Solution temperatures of equivolume mixtures of hydrocarbon and pure furfural were determined by the same method as aniline point. Investigations have shown that air oxidation of the furfural, even during the short time required for a determination of solution temperature, will seriously affect precision of the results. For this reason, furfural determinations were carried out in a closed glass apparatus through which a stream of pure nitrogen gas was passed slowly in order to exclude atmospheric oxygen. Reproducibility of the furfur:tl points is 1 0 . 2 ” C. MELTINGPOIST. The melting points were determined with a precision within rtO.05’ C. in a constant-heat conduction calorimeter developed by two of the authors (26). The accuracy of the melting points is estimated a t within rrt0.l C. I n many cases where the hydrocarbon could not be induced to crystallize, its pour point has been recorded. BOILIKGPOIST. The boiling points were determined between 0.5 and 10 mm. in a special equilibrium still, a modification of a design by Fenske (4),which provides vigorous stirring to overcome the superheating problem a t such low pressures. Pressures at the boiling point were measured by a calibrated dual-range McLeod gage. Boiling points were reproducible to within A 0 . 2 ” C., and their accuracy is estimated a t 5 0 . 5 ’ C. The heat of vaporization for each HEATOF VAPORIZATION. hydrocarbon was calculated from the boiling points a t 0.5 and 10 mm. using the Clausius-Clapeyron relation. At these lorn pressures, the assumptions involved in integration of the Clapeyron relation are minimized, and the values are estimated accurate to within f 2 % . REFRACTIVE INDEX.Using a five-place Valentine A b b e - t y ~ e refractometer, the refractive indices were measured a t 20“, 30 , and 40” C. with a precision within =t0.00003 unit. Their accuracy is estimated to be within fO.0001 unit. Prism temperature mas maintained constant to rt0.05” C. with a circulating bath. SPECIFICREFRACTION AND MOLECULAR REFRACTIOK. Specific refractions a t 20” C. for the hydrocarbons were calculated with the Lorentz-Lorene equation, using the experimental refractive index and density. “Found” molecular refractions are the product of the experimental specific refraction by the molecular weight. “Theoretical” molecular refraction values were calculated from the values of Auwers and Eisenlohr, except that 2.420 was used as the atomic value for carbon to correct for the change in the atomic weight of carbon. MOLECULAR VOLUME. The molecular volumes of the hydrocarbons a t 20” C. were copputed from the molecular weight and the density at 20” C. Calculated” molecular volumes were estimated by the additive formula of Kurtz and Lipkin (11). The “calculated” values are included in the table to illustrate the accuracy with which molecular volume may be predicted by this simple empirical method. ACKNOWLEDGMENT
The financial support of the American Petroleum Institute is gratefully acknowledged. The advice and unfailing interest of the advisory committee have been of great assistance in this work: E. M. Barber, J. R. Bates, L . C. Beard, Jr. (chairman
Vol. 47, No. 8
1940-SO), George Calingaert, G. H. Denison, L. M. Henderson, R. G. Larsen, R . F. Marschner, L. A. Mikeslta, J. H. Ramser, M.E. Spaght, Harry Sutherland (chairman 1951-), S. Tymstra, and C. R. Wagner. Valuable assistance was given in the preparation of several of the hydrocarbons by K. D. Bair, A . A. Baker, W. E. Cady, E. &I. Griest, D. M. Kimble, and R. S. Yost. T h e authors gratefully acknowledge the help of L. S. Hoover, G. H. Keff, C. N. Rowe, E. K. Sunday, and R. I€. Weaver in determining some of the physical properties, and the assistance of C. A. ,Johnson in computing the Antoine equation constants. For advice and assistance in establishing some of the physical property methods, they are indebted to M. R . Cannon, M. R . Fenske, and G. H . Fleming. Determination and examination of the mass spectra of many of the hydrocarbons by M. J. O’Xeal and others a t the Shell Oil Research Laboratory, Houston, Tex., have been very helpful. Nine of the hydrocarbons studied were supplied by C. E. Boord and associates of the Ohio State University. LITERATURE CITED
Boord, C. E., Henne, A. L., Greenlee, K. W., Perilstein, W. L., and Derfer, J. AI., IND.ENG.CHEM.,41, 609 (1949). Cannon, R l . R., and Fenske, 11. R.. IXD.ENG.CHCM.,A N ~ L . ED., 10, 297 (1938). Doolittle, A. K., and Peterson, R. H., J . Am. Chem. SOC.,73, 2145 (1951).
Fenske, A t . R., chapter on “Laboratory and Small Scale Distillation,” “Science of Petroleum,” Oxford University Press, London, 1938. Glasgow, -4.R., Jr., Streiff, A . J., and Rossini, F. D., J . Research ,Vatl. Bur. Standards, 35, 355 (1945).
Goodman, I. A , , and WTise,P. H., J. Am. Chem. Soc., 72, 3076 (1950).
Ibid., 73, 850 (1951). Griest, J. M., 113. thesis, The Pennsylvania State ‘C’niversity, 1942.
Hardiman, E. W.,and Kissan, A . H., J . Inst. Petroleum, 31, 255 (1945).
Hugel, G., Chimie et Induslr?e, 26, 1282 (1931). Kurta, S. S.,and Lipkin, 11. R., IND.ENG. CHEM.,33, 779 (1941).
Lamberti, J. AI., and Wise, P. H., J . Am. Chem. Soc., 75, 4787 (1953).
Lamneck. J. H.. and Wise. P. H.. Ibid.. 76. 1104 (1954). Landa, S.,Cech, J., and Sliva, V., Collection Czechoslh. Chem. Communs., 5, 204 (1933).
Larsen, R. G., Thorpe, R. E., and Armfield, F. A , , IND.ENG. CHEM.,34, 183 (1942). McLaughlin, R. L., Caves, R. M., and Wise, P. H., J . Am. Chem. SOC.,76, 522 (1954).
McLaughlin, R. L., Karo, T.V., and Hipsher, H. F., Ibid., 75,3233 (1953).
Mjkeska, L. A , , IND.ENG.CHEM.,28, 970 (1936). Mikeska, L. A . , Smith, C. F., and Lieber, E., J . Org. Chem., 2, 499 (1935).
Neyman-Pilat, E., and Pilat, S., IND.ENG.CHEM.,33, 1382 (1941).
O’Neal, RI. J., Anal. Chem., 23, 830 (1951). Ramser, J. H., I x u . ENG.CHEM.,41, 2053 (1949). Schiessler, R. R7., unpublished work, The Pennsylvania State University. Schiessler, R. W., Acton, W.P., and Dixon, J. A , unpublished. Schiessler, R. W., Cosby, J. N., Clarke, D. G., Rowland, C. S., Sloatman, W. S., and Herr, C. H., Proc. Am. Petroleum Inst., 23 (111),15 (1942).
Schiessler, It. W., and Fischl, F. B., to be submitted t o Anal. Chem.
Schiessler, R. W., and Flitter, D., J . Am. Chem. Soc., 74, 1720 (1952).
Schiessler, R. W.,Herr, C. H., and Whitmore, F. C., Ibid., 67, 2061 (1945).
Schiessler, R. W., and McLaughlin, R. L., chapter on “Synthesis and Purification of High Molecular Weight Hydrocarbons” in “Chemistry of Petroleum Hydrocarbons,” Reinhold, New York, 1954. Schiessler, R. W., and Rytina, A. W., J . Am. Chem. Soc., 71, 751 (1949).
Schiessler, R. W., Rytina, A . W., and Whitmore, F. C., Ibid., 70, 529 (1948).
Schiessler, R. W., Whitmore, F. C., Herr, C. H., Clarke, D. G. and Rowland, C. S.,Ibid., 67, 2059 (1945).
August 1955
INDUSTRIAL AND ENGINEERING CHEMISTRY
(33) Schmidt, 9.W., and Gemassmer, A., Ber., 73B,359 (1940). (34) Schmidt, A . W., Hopp, G., and Schoeller. V., Ibid., 72B, 1893 (1939). (35) Serijan, K. T., and Wise, P. H., J . A m . Chern. Soc., 73, 4766, 5191 (1951); 74, 365 (1952). (36) Smith, J. C., Anderson, D. G., and Rcllings, R. J . , J . C h e m . Soc., 1953, 443. (37) Suida, H., and Planchk, R., Ber., 66, 1445 (1933). (38) J\7hitmore, F. C., Coshy, 3 . S . , Sloatman, W. S., and Clarke, D. G., J . Am. Chem. Soc., 64, 1801 (1942). (39) Whitmore, F. C., Schiessler, R. W., Rowland, C. S.,and Cosby, J. N., I h i d . , 69, 235 (1947).
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(40) Whitmore, F. C., Sutherland, L. H., and Cosby, J. N., Zbid. 64, 1360 (1942). (41) Wibaut, J. P., Overhoff, J., and Jonker, E. W., Rec. traw. chim., 62, 31 (1943). RECXIVED for review -4ugust 18, 1954.
A C C E P T E D February 18, 1955. American Petroleum Institute Research Project 42. Material supplementary to this article has been deposited as Document No. 4597 with the A D 1 Auxiliary Publications Project, Photoduplication Service, Library of Congress, Washington, D. C. A copy may be secured by citing the document number and by remitting $7.50 for photoprints or $2.75 for 35-mm. microfilm, Advance payment is required. Make check or money order payable to Chief, Photoduplication Service, Library of Congress.
. Aqueous Solutions of Nitric Acid and of Sulfuric Acid
Heat Transfer Design D a t a . .
THOMAS R. BUMP AND WIL3IER L. SIBBXTT Purdue Uniwersity, Lafayette, Ind.
A
QUEOUS solutions of nitric acid and of sulfuric acid are used in many chemical processes that involve heat transfer as one of the unit operations. However, the thermal property data necessary for heat transfer and pressure drop calculations involving such solutions are widely dispersed, incomplete, and often inconsistent. Accordingly, existing data on the thermal conductivity, viscosity, specific heat, density, and total pressure of nitric acid solutions and sulfuric acid solutions have been compiled and evaluatcd. Tables of these data have been deposited with the American Documentation Institute.
be valid for pure nitric acid. The white fuming nitric acid -contained small amounts of nitrogen dioxide and water (about equal percentages by weight). Since small amounts of nitrogen dioxide and water tend to have opposite effects on the physical properties of the concentrated acid, their combined effect should have been nearly negligible.
Nitric Acid Solutions Tho recommended properties of aqueous nitric acid solutions are presented in Figures 1 t o 9. These data were extrapolated t o -40" F. and to 300" F. or to the phase boundaries of the solutions, The data for pure water and the concentrated acid have been reliably established. The boiling point curves ( 1 6 ) and freezing point curves are shown on many of the figures. The freezing point curves are based on data from International Critical Tables ( 1 7 ) , Forsythe and Giauque ( 7 ) , Kuster and Kremann (68), and Gillespie, Hughes, and Ingold (9). The thermal properties of nitric acid solutions, especially of concentrated solutions, are not dependent on temperature alone, but also depend on the amount of decomposition that has occurred. Decomposition itself depends on time, temperature, and vapor to total volume ratio. I n many types of heat transfer equipment the fluids are in the apparatus only a few secondsusually much less than a minute. Under these conditions the acid does not have sufficient time to decompose and approach conditions of chemical and physical equilibrium. The time required t o attain physical and chemical equilibrium is about 1 hour a t 200" F . and about 5 minutes at 250' F.; therefore, physical and chemical equilibrium will not be reached in most heat transfer apparatus. DISCUSSION O F RESULTS
T h s m a l Conductivity. The thermal conductivity values are presented in Figure 1. For pure water the sets of data recommended b y Wellman ( 4 6 ) and Sakiadis and Coates (58) were used. Those values recommended b y Sibbitt and coworkers ( 4 0 ) for commercial white fuming nitric acid were assumed t o
0.1
-40
-40
1 I 1 1 1 1 I 1 1 1 1 1 I I I 0 -178
Figure 1.
40 4.4
80
I20
160
48.9 71.1 TEMPE R ATU R E
267
200 240 28OoE 93.3 1196 137.8"C.
Thermal conductivity of nitric acid solutions
Data for intermediate concentrations were reported by van der Held and van Drunen ( 1 0 ) and by Riedel ( 3 6 ) . They investigated concentrations from 90 to 50% water over the temperature range from 63" t o 88" F. The values reported by Riedel are from 3 to 6 % higher than those reported by van der Held and van Drunen. The recommended values range from 2% lower to 3% higher than those of van der Held and van Drunen. The recommended values are considered to have errors of less than 5%. The data for temperatures above 140" F. assume negligible acid decomposition. Above 140' F. the chemical com-
