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Zabrodina and others classified 320 oils, from all of the principal U.S.S.R. fields, into four groups on t h e basis of the composition of t h e 200-430 "C fraction and t h e distribution of n-paraffin and isoprenoid hydrocarbons. From these data, they developed a scheme of genesis and transformation of oil which suggests a consecutive bacterial biodegradation from paraffinic t o naphthenic crudes (94B). Gurko and co-workers examined crudes from the Caspian and Baltic shores, and from east Siberia and classified them on t h e basis of their physical properties and their chemical compositions as determined by GC. T h e crudes are remarkable for their high initial boiling points. The investigators also drew conclusions as to the genetic transformations of the oils (29B). Botneva and co-workers genetically classified crude oils on t h e basis of t h e distribution of aromatic compounds boiling above 200 "C (8B). Safonova and Driatskaya correlate crude oils on t h e basis of some 18 physical and chemical analyses of t h e whole crude and several additional analyses of distillate fractions (77B). Joly and co-workers, in a regional geochemical study of Middle East crude oils, used structural analytical methods such as GC and MS. They found t h a t density and heteroatom content more related to the thermal history of the source rock, while the naphthene-paraffin ratio, content of steranes and isoprenoids, and distribution of sulfur compounds, were connected t o the type of organic matter in t h e source rock (42B). Marzec and Burczyk have suggested a correlation method based on compositional analyses by liquid chromatography and a partial characterization of the aromatic portion of either N M R spectroscopy or the n d M technique. T h e method was tested on 91 crudes from the Carpathian Flysch region and on 18 crudes from the Lubin region (58B). Chetverikova and co-workers classified dispersed organic matter on t h e basis of an examination of its nonbitumenous portion by microscopy, elemental analysis, E P R , chemical behavior toward pyridine, petrography, a n d X-ray analysis. They determined that the main difference between sapropelic and humic substances was the absence of condensed aromatic systems in the former ( 1 6 B ) . Whitehead determined the structures of several pentacyclic triterpanes in Nigerian crude oil, and was able to relate them t o modern triterpenoids, and to compounds in Green River shale (89B). Van Dorsselaer and others identified various triterpanes of the (17aH)-hopane series and t h e moretane series as ubiquitous constituents of the alkane fractions of petroleums, oil shales, coals, lignites, and other sediments. They suggest these compounds are formed by the degradation a n d isomerization of CS5precursors of the (17pH)-hopane series, which occurs in some microorganisms. Variations in the distribution of pentacyclic triterpanes may eventually be useful in developing correlations between crude oils and source rocks (87B). N o n - r o u t i n e C h a r a c t e r i z a t i o n s . Schoolery and Budde explored t h e use of carbon-13 NMR as a tool for petroleum analysis. This technique has the potential of providing accurate saturate-to-aromatic ratios more rapidly than conventional methods, and has the advantage of distinguishing betueen carbon atoms in the saturate and the aromatic moieties within t h e same molecule (15B, 82B). Krasodomaki used negative ion mass spectrometry to study the carboxylic acids, either separated from Polish petroleums or prepared by the oxidation of their distillate fractions (50B). Kuz'm ia and co-workers predicted the yields of coke obtained by delayed coking by measurements of absorption coefficients of benzene solutions of the feedstocks a t 400 and 435 nm. The predicted and experimental yields were in good agreement (52B). Roubicek and Splichal determined many of the components of coker distillate by GC (73B). Roof and DeFord designed an apparatus for the chromatographic determination of C3-C, hydrocarbons in stabilizer bottoms. T h e volatile portion of the sample is vaporized in a hollow column and analyzed by GC. The nonvolatile residue is backflushed from the tube with a liquid solvent. The solvent does not interfere with subsequent determinations (72R). Porro and Terhaar have discussed the instrumentation, and the advantages and disadvantages of double beam fluorescence spectrophotometry in the analysis of petroleum samples. The technique is particularly useful for measuring small differences between two samples of similar fluorescence ( 6 8 R ) . Nauruzov and co-workers isolated the resinous components from Mangyshiah crude oil into four fractions by chroma-
tography through large pore silica gel. T h e fractions were characterized as to molecular weight and elemental composition. UV and IR spectroscopy gave some indication of the compound types present (64B). Sturm and others characterized a heavy crude oil produced by t h e Solfrac process from t h e Bartlett Field (Kansas). A combination of techniques including GC, MS, NMK, and GPC were applied t o fractions isolated by extraction and by chromatography, to determine the major hydrocarbon and sulfur compound types (85B). McKay and co-workers have analyzed petroleum residues by the techniques originally developed by 'USBM-API Project 60 for the analysis of high boiling distillates. The compositions of residues from four oils are compared ( 5 f i R ) . Miscellaneous. Lee and others tabulated the densities, heat capacities, and UOP characterization factors for distillate fractions of three crude oils ( 5 4 R ) . Rubinstein and Strausx biodegraded Prudhoe Ray crude oil with a yeast and with a mixed bacteria culture, and compared various properties of t h e degraded oils with those of Athabasha oil sand bitumen. The similarity in properties led them to conclude that oil sand bitumen is formed by the biodegradation of conventional crude, and that the high viscosity, density, and pour point result from t h e large amount of the polar fraction which is not affected by biodegradation (74B). Bae used DTA and TGA a t high temperatures and pressures t o determine the suitability of oils for recovery by fireflooding. Fifteen oils were tested ( 5 B ) . Kasa and Bajnoczy determined traces of oil and oil products in surface waters by exciting a 1,2-dichloroethane extract of the sample a t 260 nm and measuring the fluorescence a t 340 nm (45B). Larson and Weston examined the water extractable material from crude oils by GPC on Sephadex LH-20. Some individual compounds were identified by similar analyses of standard mixtures (53B). Oren and Mackay used GPC to separate the interface fraction of a water-in-petroleum emulsion. The resulting GPC fractions were studied by IR spectroscopy (66B). Milley isolated the natural surfactants in crude oil ti?. conventional chromatography, with kieselguhr as the column packing. T h e interfacial tensions of the fractions in benzene were measured vs. water, and the chemical properties of each fraction were evaluated by IR spectroscopy and by molecular weight determinations ( 6 3 R ) . Rumsey and Pitt review the methods used by the United Kingdom Coal Research Establishment for characterizing the structure and physical properties of cokes and graphites. Some relationships between the structural parameters of graphites and their physical properties are discussed ( 7 5 B ) . Hernandez a n d Moreno characterized oil from t h e Mata-Pionche Field of Mexico and have described the yields and compositions of various distillate fractions (33B). Hatch and Matar have reviewed in general terms the composition of crude oils and the usual means of characterizing them (32B). Yokokawa compared the U.S. Bureau of Mines. t h e Standard Oil Co., and the U.K. Institute of Petroleum methods for evaluating crude oils. He described equipment requirements, data evaluation, and reliability of data (9219).
Fuels, Gaseous and Liquid J. D. Beardsley The Standard Oil Company (Ohio), Ckveland, Ohio
N a t u r a l , R e f i n e r y a n d M a n u f a c t u r e d Gases. Routine analyses and related source data for 233 natural gases from wells and pipelines in the I!.S.A. and Alberta. Canada. are tabulated for 1975 by Moore (SIC) with emphasis on helium. Kubat, Macak, Mizera, and Zachoval (,54C) describe the analysis of natural gas by gas chromatography. The integrator can he used t o calculate real density and real calorific values simultaneously. A gas chromatographic device based on the pyroelectric detector was successfully used by Guglya and Korobeinik (35C) for the determination of unsaturated hydrocarbons in the range of 0.001 to 0.0001 vol. % in natural gas from several Soviet fields containing 1 to 7.5% C 2 Ci paraffins. The optimum operating temperatures and threshold
ANALYTICAL CHEMISTRY, VOL. 51, NO. 5, APRIL 1979
sensitivities of the detector for ethylene, acetylene, propylene, butylene, hexene, and cyclohexene are given. Davidson, Garg, et al. (20C) have characterized natural gas hydrate deposits in the permafrost regions of the U.S.S.R. and Canada by nuclear magnetic resolution and dielectric relaxation. Gas chromatography was used by Akopova and Batalov (2C) t o determine the composition of a gas containing Cl.5 hydrocarbons, C02, and H2S. The best separation was obtained with a column containing A1203treated with a 10% solution of HC1 and modified with 8 wt.% oleic acid. Giarratano and Collier (32C) have calculated densities of typical liquefied natural gas mixtures under saturation and subcooled conditions using a computer program which utilizes the method of corresponding states. For the range of mixtures in this study, it is possible to determine density to f0.37~independent of knowledge of the hydrocarbon composition from an exact measurement of dielectric constant and temperature. The detection of the residual contamination level in natural gas leaving the plant or in the pipeline is discussed by Hatfield (36C). A moisture-H2S analyzer is described. Pekhota, Kamenev, a n d Byr'ko (66C) have determined COS and CS2 polarographically. T h e limits of detection are 0.1 pg/L for COS and 0.5 pg L for CS2. A Tracor model 550 gas chromatograph with ame photometric detector has been modified by Pearson (65C) to minimize losses when determining C1-C4 thiols and sulfides. T h e technique has been successfully applied to liquefied petroleum gas and t o stackgas effluents. Klass and Landahl ( 4 5 C ) have removed C 0 2 and H2S from natural gas by passing the mixture through semipermeable polymer or gelatin mixtures. Flameless atomic absorption has been used by LaVilla and Pean (56C) for the determination of trace mercury in natural gas. Cauthen ( I 5 C ) discusses the reliability of the natural gas analysis for odorant injection by chromatography or titration as a control method over absorption and flow measurement methods. A literature survey has been carried out by Knight and Verma ( 4 7 C ) for a simple, low-cost method for the field measurement of sulfide odorants in natural gas. A reaction involving methyl violet has been selected as having the potential of being developed into a colorimetric field test. Knight and Verma ( 3 6 C ) have developed a spectrophotometric method for detecting ppm levels of thiols used as odorants in natural gas. N-Ethylmaleimide was chosen from six different reagents as the most suitable for this determination. A gas chromatographic apparatus is used by Ertl, Khoury, Sloan, and Kobayashi (25C) for the determination of very small amounts (10.1 ppm) water in natural gas. A partitioning agent-glycerol on Chromosorb W-easily equilibrates with H 2 0 and is not affected by the other components of the gas mixture. S t r n a d a n d Fuxa ( 8 9 C ) describe an infrared spectroscopy method for the determination of the moisture content of natural gas. T h e infrared spectral absorption in the 3590 710 cm range is measured. Sheen ( 8 0 C ) has determined H 2 0 in natural gas by passing the gas through a high pressure glycol absorber and titrating the absorbed water with Karl Fischer reagent. T h e hydrocarbon dew point is determined by means of the dew point apparatus. Dew point and condensate are determined in small samples by Brunner and Peter ( 1 3 0 from changes in molecular weight in the gas phase under specified conditions. The density need not be known. Boni and Penner ( I O C ) have applied the sensitivity test procedure developed by Schaibly and Shuler (C.A.. 80, 52750r) to a 23-equation CH4 oxidation mechanism. Estimates are given for the sensitivity of concentrations of reactants, products, and radicals in the CH4-0-Ar system subject to simultaneous variation of all rate coefficients over a f 5 0 % uncertainty range. Terekhova and Porshneva (91C) have studied the effect of oxygen in a sample during the gas chromatographic determination of methane. For high methane concentrations, these effects are not serious, but for low concentrations they can be substantial. Gas chromatography has been also used by Yakuba (93C) to determine the composition of purified methane. Yoshida (94C) has invented gas sensors which exhibit better sensitivity toward methane than conventional sensors. These sensors are wire heating elements coated with thorium oxide catalytic supports, which is then coated with lead catalyst. A fast and sensitive gas chromatographic method was developed by Hossain, Forissier, and Trambouze (40'2) for the isothermal routine analysis of mixtures of helium,
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carbon dioxide, methane, and water. A single thermal conductivity detector, 2 Porapak Q columns, and hydrogen as carrier gas were used. Shinagawa, Hishiyama, Ito, Kayama, and Taniguchi (82C) have discovered that Brownmillerite structured ferrites of the general formula M F e 0 2 are useful as sensors for reducing gases such as H , CO, propane, city gas, and liquefied petroleum gases ( M = Ca, Sr, or Ba). Solutions of triethanolamine used to remove C 0 2 from gases in the production of hydrogen were analyzed for formic and acetic acids by Sir, Komers, and Rericha (85C). T h e acids were identified by infrared spectrophotometry or gas-liquid chromatography and determined by standard titrimetric methods. Mitera (60C) discusses the mass spectrometric and combined gas chromatographic-mass spectrometric analysis of organic mixtures such as fuel hydrocarbons. An analysis of fuel gases has been patented by Kostylev and Pleskachenko (53C). The analysis consists of a continuous oxidation of gases in the presence of a 2-stage catalyst. Simanek, Pick, and Drabek (84C) describe an improved technique for the determination of the water dew point in compressed fuel gases. The gas is bubbled through a pressurized scrubber containing silicone oil which absorbs interfering hydrocarbon components without affecting the H 2 0 dew point. Aviation Fuels. Solash and Taylor (86C)have obtained aromatics parameters from NMR spectra in JP-5 fuels derived from Western Kentucky and Utah coal and from a Green River oil shale and compared them with petroleum-derived jet fuel. The technique for determining hydrogen in aviation turbine fuel by low resolution proton nuclear magnetic resonance spectrometry is presented by Ford and Friswell ( 2 7 0 . Gladkikh, Papok, and Seregin (33C) have developed a new method for t h e determination of the oxidative thermal stability of jet fuels. The determination is based on the heating temperature required to clog the pores of a control filter by the precipitate formed during the oxidation of the fuel. A wet chemical technique for determining chromium in antistatic additives used in jet fuels is given by Borisova, Lyashenko, Rozhkov, Nazarova, and Trofimova ( I I C ) . Cunningham and Hillman ( I 9 C ) describe t h e direct determination of 2,4-dimethyl-6-tert-butylphenol in aviation turbine fuel by high performance liquid chromatography. The method is applicable to AVTAG and AVGAS fuels but not to diesel fuel. Jet fuel deposits have been examined spectrophotometrically by Zrelov, Marinchenko, Boiko, Postnikova, and Krasnaya (98C). These mechanical impurities are products of the corrosion in refinery and transportation equipment. A gas chromatographic technique has been derived by Black, Rehg, Sievers, and Brooks (8C) for the separation and identification of saturated, olefinic, 0-containing and aromatic compounds in jet engine exhaust. Motor Gasolines. Nadirov, Petrosyan, Kaldygozov, Buranbaev, Serikov, and Gafner (62C) have examined the individual hydrocarbon composition of gasolines from various reforming stages. T h e liquid products from pyrolysis of low octane gasolines were studied by Zueva, Chuevskaya, and Shadrin (99C). Stekhum, Ivanova, Sumskaya, and Mamaeva (87C)have analyzed narrow fractions of gasolines from coking residues of Ukrainian petroleums for olefins. Olefins were determined in gasoline by Schulz (78C) using capillary gas chromatography with a hydrogenation precolumn containing an aged, supported Pd catalyst and an absorption precolumn containing H2S04,H3P04,Chromosorb, and optionally HgS04. SekLyu Gakkaz Shi (79C) has published comparative test results obtained by gas chromatography on benzene, toluene, ethylbenzene, m- and p-xylene, and o-xylene in gasoline. A new evaporographic method described by Farzane and Ilyasov (26C) can be used to analyze liquids such as motor, reactive, and rocket fuels, or in combination with thermogravimetry and DTA to analyze solids. T h e quantitative analysis of gaseous products obtained in the conversion of methanol t o gasoline has been achieved by Stockinger (88C)with an on-line gas chromatographic analysis system. A total of 33 specific compounds or lumps of compounds were quantitatively detected. Bender-Ogly, Arustamova, Sultanov, and Babaev (6C) have illustrated the relationship between retention index and boiling point of C6-8 hydrocarbons from catalytically cracked gasoline. A gas chromatographic technique has been developed by Bloch, Callen, and Stockinger ( 9 C ) for the determination of individual paraffin, olefin, naphthene, and
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aromatic constituents of methanol-derived gasolines in less than 2 h. The method has been used to show that methanol-derived gasolines are much higher in olefins and naphthenes. Budzak and Clinton (12C) monitor the octane number of a gasoline stream by measuring a parameter of an oxidized sample of the stream correlated t o octane number. An equatiton for the calculation of the octane numbers of straight-run gasolines, based on gas-liquid chromatographic data, is given by Dracheva, Bryanskaya, Sabirova, and Zhurba (23C). The effect of the amylene content of the raw material on the octane number of alkylate gasoline has been studied by Kirilin and Sumanov (44C). They have found that octane number decreased as the amylenes content increased. Baudino, Chloupek, and Crowley (5C) have developed an analyzer to determine the pressure increase with time resulting from the vaporization of a fuel sample at constant volume, temperature, and initial reduced pressure. The pressure vs time curve is unique for each fuel. Curves of several gasolines containing alcohol are given. Ruo, Selucky, and Strausz (77C) have developed a high performance liquid chromatographic method for the determination of tetraethyllead in gasolines. The method is based on the separation of tetraethyllead from other UV-absorbing material on silica gel and quantification of the UV detector response. Tetraethyllead is determined rapidly and accurately in gasoline by Garcia Escolar and Contreras Lopez (30C). The sample is refluxed with a carbon tetrachloride solution of trichloroacetic acid, extracted twice with water, and the extract is titrated complexometrically. A Roentgenboy Lab X-ray fluorescence spectrometer has been used by Kaegler, Tillmanus, and Hebold (41C)to determine lead in gasoline. Knof and Albers (48C) have modified a single focusing MS instrument for the quantitative determination of tetramethyland tetraethyllead in motor fuels. An injection block similar to that used in GLC has been incorporated. Trace lead in gasoline has been determined by atomic absorption spectrometry by Madec and LaVilla (58C). The sample was prepared for analysis by refluxing with HC1, then H 2 0 , complexing with diethylammonium diethyldithiocarbamate and extracting with xylene. Robinson, Kiesel, Goodbread, Bliss, and Marshall (76C) have developed a carbon furnace atomizer which can be attached directly to a gas chromatographic column. The atomizer has been tested by determining tetraalkyllead in gasoline and organic lead compounds in air. A combination gas liquid chromatographic-atomic absorption spectrometric method has been used by Chau, Wong, and Saitoh ( 1 6 C ) to determine tetraalkyllead compounds in the atmosphere. This method could also be applied to petroleum. Tetraethyllead and tetramethyllead have been extracted from gasoline by aqueous iodine monochloride and analyzed polarographically by Kunic and Vicevic (n'5C). The results were comparable to those obtained by an atomic absorption method. Rajkovic (75C) has devised a suitable apparatus for the control of toxic gases and fumes expelled from the nitric acid treatment of the iodine monochloride extract of tetraethyllead. The apparatus consists of existing glass extension pieces produced in Yugoslavia factories. An electrochemical detector for lead alkyls has been patented by Olson (64C). Zelaskowski and Carlisi (96C) describe a rapid field analysis of lead in gasoline by colorimetric comparison. T h e direct determination of manganese in gasoline by atomic absorption spectrometry in the nitrous oxide -hydrogen flame has been accomplished by Lukasiewicz and Buell (57C). The results obtained agreed with those by X-ray fluorescence analysis. Flameless atomic absorption spectrometry has been used by Driscoll and Clay (24C) for the direct determination of phosphorous in gasoline. T h e isotope dilution method of analysis was expanded by Carter, Donohue, Franklin, and Stelzner (14C) to allow the addition of 220 enriched stable isotopes to a single sample. Water and gasoline thus prepared were analyzed for trace metals b y spark source mass spectrometry. Abashin, Mamedova, Buniyat-Zade, and Markaryan ( 1C) have determined the heat stabilizer thioalkofen MBP in gasoline by means of polarography. A detection method of illegal diluents (such as benzene, toluene, xylene, or kerosine) in gasoline or light oil has been patented by Yoshinaga and Hama (950. The method comprises the addition of a colorless chromogenic compound, such as crystal violet lactone, to the sample and stirring with an open end tube containing
an oxidizing agent such as activated silica gel clay. The degree of color change in the clay indicates the amount of cutting agent present. Svajgl, Holle, and Vitovec (9OC) have determined trace amounts of chlorine in gasolines by coulometric titration with biamperometric indication using a novel commercial titrator model. Flameless atomic absorption spectrometry has been used by Potter (70C) to determine rhodium in platinum-rhodium loaded automotive catalyst material. Konopczynski and Charnicki (50C) describe two brass vessels for the storage of combustion gases from internal combustion engines. Anghelache ( 3 C ) has determined the principal pollutants in exhaust gases of internal combustion engines by gas-solid chromatography. An apparatus for sampling the exhaust gases is illustrated. The concentration of 14 elements in samples of soil and grass in the vicinity of a hig',way have been determined by Oakes, Furr, Adair, and Parkinson (63C) using neutron activation analysis. Black, High, and Sigsby (7C) have applied total hydrocarbon flame ionization detectors to the analysis of hydrocarbon mixtures from motor vehicles with and without catalytic emission control. Polycyclic aromatic hydrocarbons present in exhaust gas condensate from motor vehicles have been separated by gas chromatography and characterized by mass spectrometry by Grimmer, Boehnke, and Glaser (342).About 150 different polycyclic aromatics were thus separated whose concentration was greater than 1 mg/L. Konopczynski (51C) has determined aldehydes and ketones in combustion gases from piston engines spectrophotometrically using 2,4dinitrophenylhydrazine. A glass capillary column has been used by Hoshika and Takata (39C)to determine benzaldehyde and 0-,m-, and p-tolualdehydes in car exhaust gases. These same authors (38C) have also separated 2,4-dinitrophenylhydrazonesof 10 aliphatic aldehydes, 8 aliphatic ketones and 4 aromatic aldehydes using glass capillary columns. This gas chromatographic procedure has been applied to the analysis of automobile-exhaust gases and cigarette smoke. With the use of 3 gas chromatograph columns, Kojima and Seo (49C)have concentrated and identified carbon tetrachloride, chloroform, tri- and tetrachloroethylene and 1,2-dibromomethane in automobile exhaust gases. Cornea, Cracium, and Anghelache (18C) describe a modification of the Saltzman method for the spectrophotometric determination of total oxides of nitrogen in exhaust gases from internal combustion engines. A coated piezoelectric crystal detector has been used by Karmarker, Webber, and Guibault (43C) for the measurement of sulfur dioxide in automobile exhausts and industrial stack gases. Prescott and Risby (71C) have reported a method for preparing platinum bis( l,l,l-trifluoro-2,4-pentanedionate), together with the analysis of ruthenium in automobile exhaust emissions by negative ion chemical ionization mass spectrometry. Several formulas requiring only partial analysis of exhaust gas are discussed by Ghezzi and Ortolani ( 3 1 0 and proposed to calculate air-fuel ratios of 4-cycle engines. For determining breather losses, Prokhorov (72C) has calculated average concentrations of gasoline vapors in a vapor-air mixture discharged from a tank. Dell'Acqua, Bush, and Egan (2ZC) have identified components of gasoline in ground water by gas chromatography. Although the components are not as well separated as on capillary columns, the method suffices for the qualitative differentiation of sources of contamination. Distillate Fuels. Equations have been derived by Chuprin, Zhorov, Dianov, Chekhovskii, Andrienko, Pogrebnyak, and Kopeikin (17C) for blending a diesel fuel having a predetermined flash point, viscosity, and sulfur content from 3 different components. Petrovic, Stojanovic, and Vitorovic ( 6 8 C ) have obtained a correlation between the n-paraffin content of middle distillates and some basic properties such as cloud, pour, density, viscosity, and distillation range. ASTM D 976 has been used by Kalmutchi and Conrad (42C) for determining cetane index of domestic diesel fuels which contain no kerosine. For diesel fuels with up to 55% kerosine, they use equations. Azizov and Ryabova (4'2) have separated naphthenic acids from diesel fuels by adsorption and elution. The naphthenic fraction is further saponified and separated from fuel and bituminous impurities. Leaching has been used by Shikhalizade, Yusufzade, Safarov, and Sitaraman (81C) to separate naphthenic acids from diesel fuels. The acids are then distilled to obtain narrow fractions and a residue. A
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photometric method is described by Gallyamova, Yudina, and Abdulkhakimova (29C) for determining the resinous substances in hydrorefined diesel fuel used for purifying the reaction gases formed by the dehydrogenation of isopentanes and isopentenes or Cr-Ca-Ni phosphate catalysts. The results agree with values obtained by steam distillation. Shishkina, Chertkox, and Kirsanova (83C) have made a study of the products of natural liquid phase oxidation formed after long storage in jet and diesel fuels by extracting and identifying oxygen compounds. Of the oxygen compounds identified
