petroleum research laboratory has been reviexved b y Bird (BA); he deals with analysis of surface layers of lubricants on metals and specimen sections of bearing metals. Several papers from abroad indicate the growing use of modern methods there; such reviews as those of Ternoysksya (41A),Keil (19A),and Luther and Louis et al. (29A) are indicative. The role of statistics in analysis was paid attention b y Calder (4A). The ranking of laboratories and evaluating of analytical test methods used in cooperative test programs, as is very commonly done in petroleum analytical laboratories, n a s discussed b y Lashof (2IA). Most interesting is a neFv slant on the construction of specifications for petroleum products as described by Cranston and Gammon (6-4).
Crude Oil J. L. Ellingboe, Marafhon Oil Co., Findlay, Ohio
A
for the analytical batch distillation of petroleum crudes on a packed column was reported by Schwartz (1SB). This proposed dist,illation t'echnique was shown to be faster than the T7igreux column method, Jvith good agreement between the tvvo. The time advantage is obtained because a smaller sample is fractionated a t a lower reflux ratio. Gaylor, Jones, Landerl, and Hughes (5B) have developed a gas chromatography method for the simultaneous determination of crude oil boiling range distribution and hydrocarbon-type distribution. The exact location of a peak is achieved b y assigning a major group number and a partial relative retention time. A qualitative characterization of major peaks and shoulders was done by using a time-of-flight mass spectrometer attached to the detector vent of the gas chromatography unit. The boiling range distribution obtained for paraffinic crudes was close to the dist,illation curves from an efficient fractionating column. Typical analyses of heavy naphtha and crude oil are given. Infrared spectroscopy was used by Leutner (9B) to make approximate estimations of certain structural groups in crude oils from the Vienna Basin. By this method, a view of the hydrocarbon composition of an oil is obtained quickly. Karbasian (7B) reviewed the procedure for the evaluation of crude oils a t Abadan, Iran. A. detailed analysis of a crude oil from the .Ihwaz Field is shonn. Kerenyi (8B) has continued his studies of Hurigarian domestic and imported petroleum. I n this paper he describes a process for the laboratory investigation of crude oil b y which the RAPID hfETHOD
158 R
ANALYTICAL CHEMISTRY
chemical composition and economic value can be accurately estimated. This involves distillation; fraction investigation with graphical evaluation of the results. Schenck and Eisma (12%) developed a gas chromatography method to determine n-alkanes in crude oils and rock extracts. A gas chromatography column was placed in series with a column filled with molecular sieves. Two chromatograms &*ere obtained, with and lvithout n-alkanes, thus permitting their determination and distribution. X unique sampling analysis method for crude oil directly from the well was developed b y Giraud (6B). The analysis is done by gas chromatography: specific peak areas for n-paraffins were established. Nestler, Triems, and Heinze (10B) have also reported a method for the determination of the paraffin content of crude oils. The crude is dissolved in hexane and filtered over fuller's earth. After removing the hexane, the waxes are crystallized and separated by precipitation from an acetone-toluene solution. Reproducibility is about 0.5 weight per cent for paraffin contents of 10 to 20 weight per cent. Seutral resins in crude oil or wax were determined b y a procedure developed b y Tronov and Khamzina (16B). Asphaltenes are first separated and the sample is then split into two portions. One is treated with silica gel and then extracted with petroleum ether. The ether extract is combined with the unextracted portion, the optical density measured, and the resin content calculated b y a formula derived b y the authors. Tumasyan and Babalyan (16B) measured the adsorption of asphaltenes from crude oil and synthetic mixtures of asphaltenes in kerosine-benzene solutions on sand and quartz. They observed the largest asphaltene adsorption from the synthetic mixture using sand as the filtration media. X small angle x-ray scattering study of the colloidal nature of petroleum by Dwiggins (ZB), showed that colloids derived from seven crude oils had different average Guinier radii of gyration, and some polydispersity. Comparison of these results with those of other studies suggests the colloids seen b y x-ray scattering are the same as the asphaltic-rich colloids seen in ultracentrifuging. The small angle x-ray method shows promise for further study of colloids in petroleum. Forney, Gulbrandsen, and Borup (4B) determined the salt content of crude oil by measuring the conductance of a solution of the crude 011 in a mixture of xylene, methanol, and butanol. The apparatus was calibrated using a mixture of NaC1, CaC12, and MgC12; 7 to 2 to 1, respectively. Re-
sults were in good agreement with those obtained using a conventional extraction method. Apparatus was also developed to analyze a plant stream at 3to 60-minute intervals, with a single analysis requiring about two minutes, Farley and Leonard (SB) developed a procedure for the determination of the salt content of heavy crude oils and asphalts. The crude or asphalt is dissolved in phenol-chloroform and extracted with a 0.1% solution of sodium or ammonium nitrate in water. The aqueous evtract is centrifuged, and an aliquot titrated for chloride with silver ion. The method is fast and accurate. Crude oil as light as 27' *\PI and asphalt as hard as 10 penetration have been analyzed successfully. Trace amounts of vanadium in hydrocarbons mere determined b y Roberts (11B) using electron spin resonance. The samples were solidified to avoid inherent errors when samples are run in the liquid state. Ultrasonic atomization of oil samples diluted 1: 1 m-ith alcohol gave improved flame photometric sensitivity when compared with other methods in the detection of alkali and alkaline earth metals. -4ugsten (1B) also reported a significant reduction in analysis time. The results suggest this technique can be adapted to the quantitative determination of sodium crude oils. Sugihara and Garvey (I@) obtained higher recoveries of etioporphyrin I and mesoporphyrin IX when they substituted formic acid for acetic acid using the hydrogen bromide demetalation method for vanadyl porphyrins. This modified method has been used in the analysis of asphaltenes and crude oil.
Fuels K . I. Shull and I. D. Beardsley, The Standard Oil Co. (Ohio), Cleveland, Ohio
V
ERNET AND KNIAZEFF (Iloc) describe methods of determining viscosity, thermal conductivity, and latent heat of liquefied natural gas a t 2 - 175' C and 5 1067 psi, but no experimental results are given. An apparatus constructed with practically inert niaterials is being used for measuring viscosity of a corrosive natural gas b y Lazarre, Martin, et al. (sac). Sens and Sallaberry (97'2) discuss the theory of density measurement of natural gas. They have studied both a static and a dynamic densimeter. Gebert, Lugt, and Herbst (34C) have worked up a simple gravimetric technique for density measurement. They have compared results with those obtained on six different instruments of four types. Prahacs
