Petroleum J. M. FRASER Union Oil Company of California, Brea, Calif. 92521
This is the thirteenth review of analytical chemistry in the petroleum industry (IA-12A) sponsored by the Division of Petroleum Chemistry of the American Chemical Society. Its objective is to cover the most important and relevant publications appearing essentially in 1974 and 1975. Specifically, it covers the papers abstracted in Chemical Abstracts, in the American Petroleum Institute Refining Literature Abstracts, and in Analytical Abstracts (London)for the period of July 1974 through June 1976. Thus this review begins where the previous one ended and the general format of previous issues is being continued. References conform to the Chemical Abstracts "Guide for Abbreviating Periodical Titles." In addition, when a reference publication might not be readily available, the abstract journal has been appended to that for the original source. The ab-
breviations C.A., A.P.I.A., and A.A. are used to identify the abstract journals cited above. These abbreviations are followed by the volume number, the abstract number, and the year. The abstract searching was done by J. F. Hickerson, Exxon Co., U.S.A.; R. W. King, Sun Oil Company; C. A. Simpson, Mobil Research and Development Corp.; and J. M. Fraser, Union Oil Co. of California. The collected abstracts were then screened and organized by subjects. Each collection of abstracts was then additionally reviewed, screened, and organized by fourteen authors of the eleven subjects or subsections which follow. The generous assistance of the abstractors and of the authors, many of whom have contributed to previous reviews, is very much appreciated and the production of this review is due to their combined efforts.
Crude Oils
extracted with EtOH-C& were more highly branched than those extracted with CHCls (37B). Heterocompounds. Drobot and Presnova determined the amount, composition, and distribution of the main types of sulfur compounds from selected crudes of the Sikerian Platform (24B). Numanov et al. employed catalytic micro-hydrodesulfurization, followed by MS analysis to determine the structures of sulfides in two crude oils from south central Asia. Mono- and bicyclic sulfides accounted for 78-84% of the total sulfides in the samples examined (73B). Numanov and coworkers characterized other high sulfur (5.0-6.2% S) crudes from the same general area and found mercaptans and sulfides the predominant sulfur compounds in those fractions boiling below 200°, but disulfides predominated in those fractions boiling over 200' (74B).Khaitbaev et al. analyzed the sulfur compounds from petroleums of this area and confirmed the above findings, but added more detailed data (54B). Akhmedova attempted to establish a relationship between S, N, and silica gel resin content, and also between their content and depth of occurrence and specific gravity of some Azerbaidzhan crudes. However, the correlations were not close as might be hoped (3B). Orr studied changes in sulfur content and in sulfur isotope ratios with thermal maturation, using the Big Horn Basin (Wyo.) Paleozoic oils. In addition to the trends usually observed, he noted that during thermal maturation in high temperature ( >80-120') reservoirs with sulfate present, nonmicrobial sulfate reduction may take place with negligible isotopic fractionation (75B).Ho et al. determined the classes of sulfur compounds in 78 crude oils from many of the world's major fields. Oils abundant in unstable compounds, such as nonthiophenic sulfides and benzothiophenes, were classed as immature. Those containing more of the stable dibenzothiophenes were classed as mature, while a third group of intermediate distributions was termed altered (44B). Gusinskaya et al. separated the nitrogen bases from a series of Sakhalin crudes by ion-exchange and adsorption chromatography, and used IR and NMR spectroscopy to determine their general structure (38B).Brodskii and co-workers continued this study, showing that pyridine derivatives constituted 18-30% of the basic extract, quinoline derivatives 5060%, and acridine-benzoquinolines 12-20%. Most of the heteroaromatic cores were present as cata- or peri-condensed systems with one to three naphthenic rings. The majority of substituted species had one relatively long alkyl chain and several methyl or ethyl groups ( I 1 B ) . Sevast'yanova et al. determined the ratio of basic-to-total nitrogen in 29 Ukrainian crude oils, and the distribution of primary, secondary, and tertiary amines in each sample (88B).
F. C. Trusell Marathon Oil Company, Littleton, Colo.
Sampling. Sampling is often the weakest link in crude oil analysis. The Reservoir Fluids Group of the Chambre Syndicale de la Recherche et de la Production du Petrole et du Gaz Nature1 has recommended procedures for obtaining either surface or bottom-hole samples (81B). Hydrocarbons. Urazgaliev et al. determined the distribution of n-paraffins in 20' and 50' cuts of Mangyshlak petroleum boiling below 510'. They tabulated the physical property data from these fractions and proposed an explanation of the observed pour properties of the oil based on the crystallizing properties of its constituents (95B). Abidova et al. distilled Uzbekistan oils into five fractions boiling below 200' and determined the individual aronfatic hydrocarbons in them by GC. Oils from deeper strata contained substantially more aromatics than shallower oils (2B). Kasamatsu analyzed the diaromatic fractions of three lowsulfur Southeast Asia crudes and six high-sulfur Middle East crudes by GC and by IR spectroscopy, and found 2-monoalkyl naphthalenes, and naphthalenes with one methyl group on each ring were more abundant in the low-sulfur oils (52B). Zhurba et al. employed GC and MS to determine the hydrocarbon-type distributions in the 140-180' and 180-240' fractions of several eastern Ukrainian crude oils, and related their findings to the ages of the containing formations (103B). Kuklinskii and Pushkina have developed a formula for determining adamantane in crude oils based on the IR absorbtivity of a key CH group vibration, and used it in the analysis of 34 USSR crudes. They found the importance of adamantane structures falls sharply in fractions boiling above 300 'C (60B). Garmasheva analyzed the oils from the bitumen fractions of Pripyat Basin crudes. He identified tetralins, indanes, benzonaphthenes, dibenzonaphthenes, and tricyclic naphthenes, and determined the number of carbon atoms in paraffinic chains to ranges from 6 to 20 (29B). Guseva and Chernova separated asphaltenes from several samples of recent sediments by extraction with CHC13 and with EtOH-C&. The asphaltenes were studied by x-ray diffraction, and though they were in the initial stage of diagenesis, they already had aromatic structures similar to those of asphaltenes extracted from crude oils. The asphaltenes
ANALYTICAL CHEMISTRY, VOL. 49, NO. 5, APRIL 1977
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