Chemical Structure
of Lubricating
Oils L.A. MIKESKA Standard Oil Development Company, Elizabeth, N. J.
~~
This report presents a study of the structure of lubricating oils on the basis of synthetical rather than analytical work. Several series of hydrocarbons consisting of alkyl derivatives of benzene, naphthalene, and diphenyl have been prepared to determine the effect of chemical structure on their chemical and physical properties. A relationship is established for these hydrocarbons between their viscosity characteristics and chemical structure. This study includessuch structuralfactorsas length, unsaturation, and branching of side chains. The effects on viscosity of other characteristics such as cyclization, reduction of aromatic to hydroaromatic rings,multiplicity of side chains, and allocation of the latter in the nucleus, are also considered.
of petrolcum oils has rrniaincd unabated since the inception of the industry. The early investigations of I'clouze and C'utiours (W), Warren (,$I!; Schorlemmer (ST), and Beilstein and I., and Cahours, A , , 60mpt. r e d , 54, 1241 (1862) ; 56, 506 (1863) : 57, 62 (1863). (33) Rue, W.de la, and Muller, H., Proc. Roy. SOC.(London), 8, 221 (1856). (34) Sachanen, A,, and Wirabianz, R., Erdol u. Teer, 9, 187 (1933); Petroleum Z., 25, 867 (1929). (35) Schneider, J., and Just, J., 2. wiss. X i k r o s k o p . , 22, 981 (1905). (36) Schorlemmer. C., Chem. S e w s , 7 , 157 (1863). (37) Schorlemmer, C., J . Chem. SOC.,15,419 (1862). (38) Spilker, -1.J . , Brennst0.f-Chem., 7, 261 (1926); 2. a n g e u , Chem., 39, 997 (1926). (39) Sulliran, F . W., Jr., Voorhees, T,,Neely, A. TT., and Shankland, R . T., ISD. ESG. CHEH.,23, 609 (1931). (40) Tlugter, J. C . , \Taterman. H . I., and Westen, H. A. van. J. Inst. Petroleum Tech., 18, 736 (1932). (41) Karren, C . >Proc. I.,A m . Acad. d r t s Sci., 27, 56 (1891). (42) Wilson, W.J., and .Illibone, B. C., J . Inst. Petroleum Tech., 1 1 , 180 (1925). (43) Zrlinsky, S . D., and Kaznnsky,B. .I., B e r . , 64, 2265 (1931).
RECEIVED .ipril 18, 1936
Publication of tables with structural formulas made possible through the codperallon and financial assistance of the Standard Oil Development Comprtny.
Phase Equilibria in Hydrocarbon Systems XV. Mixtures of Methane and B. H. SAGE, D. C. WEBSTER, AND W. N. LACEY California Institute of Technology, Pasadena, Calif.
@A
S A PART of the general study of the ther-
modynamic properties of naturally occurring hydrocarbon mixtures being conducted by Research Project No. 37 of the American Petroleum Institute, an experimental study of some of the mixtures of methane and a crude oil has been made. The temperature range investigated was from 70" to 220" F., and each mixture was studied a t pressures from 300 to 3000 pounds per square inch. The seyen mixtures investigated varied systematically in composition from the crude oil to mixtures containing about 10 mass per cent methane. The measurements included (a) specific volumes as a function of pressure, temperature, and composition, and (b) specific heats as a function of temperature and composition a t a given constant volume. It was not feasible to investigate the behavior of mixtures containing higher concentrations of methane than those cited above because of the separation of a second liquid phase, apparently asphaltic in character. The separation of this third phase may be due to the low solubility of asphaltic material in hydrocarbon liquids containing appreciable quantities of the lighter compounds. This additional phase rendered further measurements useless as the attainment of equilibrium was quite uncertain.
.
Previous articles in this series appeared during 1934 and 1935, and in January, February, April, May, and June, 1936
a Crude Oil'
I
I Specific volumes and speqific heats of several mixtures of methane and a crude oil from the Santa Fe Springs Field, Calif., were determined. Several diagrams illustrating the behavior of such mixtures are shown.
Materials The crude oil chosen for this x-ork was a composite sample from several of the important producing zones in the Santa Fe Springs Field of California. The same oil was used in earlier studies (7, 8). The physical properties of the oil sample were as follows: gravity, 34.9" A. P. I. a t 60" F.; specific gravity,2 0.8495 a t 60" F. and 1 atmosphere; flash point, below 80" F.; pour point, below 0" F.; viscosity, 42 seconds (Saybolt Universal) a t 100" I?.; kinematic viscosity, 4.73 centistokes a t 100" F.: water and sediment by centrifuge and by distillation, trace. 4 sample of this oil was distilled in a laboratory column to determine directly the quantity of each of the hydrocarbons from methane through pentane. The residue 2 T h e term "specific gravity" is here used t o denote the ratio of the weight of a given volume of the material a t a specified temperature and pressure to the weight oi the same volume of water a t its maximum density a t atmospheric pressure.
