Rodionova e t al. (3051)studied the high molecular weight hydrocarbons extracted from rocks. Shlyakhov et al. (3411, 3421) analyzed petroleum for isoprenoid alkanes. Jonathan et al. (1651) developed a rapid technique for the analysis of light hydrocarbons in rocks. Marschner and Winters (2351) showed that the n-alkanes present are indicative of the source of ozocerites. Bordet and Gourlia (481) developed a rapid method of analysis for multicomponent mixtures based on the use of very short columns and computer assisted peak deconvolution. Abdeddaim et al. ( I A ) extended their analysis technique which involves the use of temperature programming and reverse carrier flow. Chernyak (621)determined the carbon-to-hydrogen ratio in light gasoline by gas chromatography. Laub et al. (2161)examined the relationship between specific retention volume and relative formation constants to explain the behavior of aromatic hydrocarbons on dibutyltetrachlorophthalate. Engewald et al. (1031) used gas-solid chromatography for the structural identification of cyclododeca-1,5,9-trienes. Morozova et al. (2531) analyzed the diastereomers of alkanes with three asymmetric carbon atoms, and also a series of C10-C12 dimethyl alkanes (2521). Usova et al. (3891)reported the optimum conditions for the determination of impurities in cyclododecane. The use of inverse chromatography for the analysis of high boiling fractions was discussed by Kozlov et al. (1861) and Shlyakhov et al. (3401). Pyrolysis gas chromatography was used by Seeger et al. (3291)to investigate the sequence length distribution and homogeneity of polyolefins. Herain and Mokra (1471)compared the reproducibility of different pyrolyzers using model hydrocarbons. Berezkin et al. (291) reviewed chemical methods of preparing standard mixtures as references for gas chromatography. Smol'skii et al. (3521)reported their studies on the use of preparative gas chromatography for the identification of gasoline components. Hussey and Parcher (1541) derived a retention volume equation for frontal chromatography which corrects for gas phase viscosity effects. The equation was applied to the chromatography of n-hexane in n-octacosane. Fuzita et al. (1201) separated polycyclic aromatic hydrocarbons using hexane as the mobile phase in a supercritical fluid chromatography. Lanser et al. (2141)discussed the precision and errors encountered in the use of the mass chromatograph. Miscellaneous. The hydrocarbon structure of kerogen from Green River oil shale was examined by Schmidt-Collerus and Prien (3241). The major portion of the hydrocarbon skeleton consisted of a 3-dimensional heterocondensed matrix of protokerogen sub-units of the tetralin, terpenoid, and steroid type connected by longer-chain alkanes and isoprenoids. Schmidt-Collerus et al. (3251)also examined the spent shale ash from Green River oil shale retorting in order to evaluate the environmental impact of trace quantities of polycondensed aromatic compounds residual in the shale ash. Laus et al. (2171)studied the extent to which 3,4-benzopyrene genetically bound with kerogen from kukersite shale is transferred to products by thermal decomposition. The percentage transferred does not exceed 5% of that present, most of which is in the semi-coking tar irrespective of the severity of the thermal decomposition. Berthold (401) discussed the possibilities for analytical distinction between biogenic hydrocarbons, mineral oil hydrocarbons, and pyrolytic exhaust gas components. Pyrolytic compounds and motor gasolines could be distinguished by the presence of anthracene which is absent in biogenic extracts. A symmetrical distribution of alkyl benzenes was judged indicative of petroleum product contamination. to lo-% of oil in Epimakhov et al. (1041)determined raw materials, waste waters, etc., by adsorption polarography on a mercury drop electrode. Stefanescu (3611) reviewed the quality requirements for petroleum products. Creanga (711) reviewed the chemical composition of petroleum and hydrocarbons with special regard to Romanian petroleum. Iordache et al. (1561) determined the distribution of n-paraffins in Romanian kerosine and gasoline. Stekhun et al. (3621)determined the chemical composition
of coking distillates. Mikhailov et al. (2411)determined the individual hydrocarbon composition of liquid paraffins. Mamedova et al. (2311)determined the isomer distribution of octenes from polymer gasoline. Ward (3941) reported the long term effects of benzene in C57BL/6N mice. Soboleva et al. re orted the synthesis and isomeric conversions of the spiroi.41nonane (3541)and spiro[4,5]decanes (3551).Berman and Denisov et al. (321)reported the multistep synthesis of 4-methyltetracyclo[6.Z.l.02~713~6]dodecane and other tetracyclic CIrC14 hydrocarbons. Berman, Denisov, and Petrov (331)prepared a series of c15-Cl6 adamantane type hydrocarbons. A large number of authors reported hydrocarbon compositions of straight run fractions of USSR crude oils. Gasoline range results were reported by Khodzhaev et al. (1751), Khaitbaev et al. (1741),Egiazarov et al. (981,991),and Abidova et al. (31,41). The gas oil range was reported by Kuklinskii and Pushkina (1921),Przbylski and Rychlik (2921)and Zimina et al. (4121). Distillates were reDorted bv Kurbskii et al. (2121).Sereienko et al. (3311),Maksimova et al. (2301),Kulinskii et al. r1971), Hala and Kuras (1361),and Gusinskaya et al. (1341). Pushkina et al. (2931),Papazova and Pankova (2751),and Mardanov et al. (2321)reported the hydrocarbon composition of kerosine fractions. Ushakova et al. (3881)examined the triterpanes in Baku crude. Rudakova et al. (3101)separated the solid paraffinnaphthenic hydrocarbons from Dolinski crude oil by complex forming with urea and thiourea. Mikhnovskaya et al. (2421) exhaustively examined the composition and structure of Surgutsk petroleum. The distribution of hydrocarbons and resins in the deasphalted concentrate from Sangachaly crude was reported by Kuliev, Samedova, et al. (1981).
Metals in Oils R. E. Terrell Gulf Research and Development Company, Pittsburgh, Pa.
Flame Spectrometric Methods. The word is trace and the game is atomic absorption (AAS). Of the 91 papers listed, 35 used this discipline. Hahn (25J)absorbed mercury in natural gases with an aqueous solution of 10%HzS04 and 1%KMn04 and determined its concentration by flameless atomic absorption. The graphite atomizer was also used by Heinrichs (27J)after mercury was separated from petroleum by evaporation, formed into a gold amalgam, extracted with "OB, and deposited on a gold cathode. Knauer and Milliman ( 3 7 4 reported levels of mercury when petroleum samples were decomposed by digestion with H2S04-HN03 or in a Wickbold 02-H2 system. The volatilized mercury was collected in acid KMn04 solution and detected by cold-vapor AAS. A carbon rod atomizer modified by Araktingi et al. ( 2 4 proved rapid and reliable for trace elements in crude oils. Effects of different sheath gases were discussed. Robbins et al. ( 6 6 4 and Runnels et al. (69J)discussed the use of a carbon rod atomizer and a graphite furnace atomizer to detect beryllium a t nanogram levels. Heated vaporization was also proven useful for the determination of manganese as Robbins (65J)discussed micro standard addition and dilution with tetrahydrofuran to give optimum peak height. Copper in naphtha was reported by Sinha and Banerjee (76J)using a double capillary aspiration system and aqueous standards. Viscosity corrections are required. Additive elements continued to be studied by atomic absorption. Hopp (29J)reported an aqueous emulsion method for zinc, calcium, barium, and magnesium. The technique avoided inflammable solutions. Oshima et al. ( 5 7 4 discussed a single standard method with halogen additives for various elements in gasoline and lubricating oils. Abu-Elgheit ( I J ) described a rapid, direct determination of cadmium a t 0.01-0.08 pm while Robbins and Walker (67J) extended cadmium Ltection limits to nanogram levels by digestion with ANALYTICAL CHEMISTRY, VOL. 49, NO. 5, APRIL 1977
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H z S 0 4and ashing. Nowak (545) included analyses for antimony and lead with cadmium using flame and heated-vaporization AAS. Several Atomic Absorption Reviews were written by Lush (455) who compiled 78 references to trace element analysis. Lang et al. (405)developed a critical evaluation of 220 references. They stressed the need to check the correctness and accuracy of methods. Vigler and Gaylor (835) grouped abstracts of papers presented at the 166th National Meeting, American Chemical Society, according t o Society Divisions. The importance of nickel and vanadium porphyrins continued to hold attention as Vavrecka et al. (815) used these compounds for calibration standards for direct determination of the metals. They reported closer conformation to the Lambert-Beer law than oxide standards; however, the accuracy of vanadium is affected by the vanadium bonding and matrix so a standard addition technique was recommended. The standard addition technique was also used by Everett et al. (145) to reduce matrix effects at 1 ppm levels. For oils containin 0.01-0.1 ppm, the vanadium was extracted with 2 M HC1. h a y and Presley (495)claimed a saving of time by charring and atomizing as a C C 4 solution in a graphite tube. Grey (235)also reported on the determination of trace nickel and vanadium in petroleum. Viscosity differences affect the determination of trace iron in crude oil so Ibrahim and Sabbah (305) recommended matching standards and unknowns. Everett, West, and Williams (145)used a carbon-filament reservoir for the detection of tin at 0.1 ng and less. Hz and Ne were used as sheathing gases and results were given for both aqueous and organic media. Walker (845) reported on selenium and Grey (225, 235) on nickel, vanadium, cobalt, and molybdenum. Moving away from the usual reporting of one or two elements by atomic absorption, Vigler and Gaylor (825) determined 23 elements in the range 1ppb to 5 ppm by ashing after absorption on magnesium or potassium sulfonate and solution in dilute acid. A graphite capsule-flame atomizer was used by Katskov et al. (355) to determine 27 elements. Lower limits of detection are 0.001 to 0.1 ppm. The analysis of ten samples for ten elements took 4.5 h. Fletcher and Collins (215)determined 12 elements in oil field brines using the method of additions to overcome large matrix differences. For brines where concentrations of elements are low, they recommended a graphite furnace. Detection limits for 17 elements were listed by Kaegler (315) outlining some problems with the direct analysis of organic matrices. Araktingi, Chakrabarti, and Maines ( 2 5 ) used a carbon-rod atomizer and metal cyclohexanebutyrate salt standards to determine cobalt, magnesium, sodium, tin, cadmium, zinc, and aluminum in crude oil. Serbanescu et al. (725)listed conditions and detection limits for ten elements in fuel oils and petroleum cokes using airacetylene flame. NBS standards in xylene served Rozo (685) for the determination of copper, iron, nickel, lead, and vanadium in various petroleum products. A radiofrequency spectrometric source adapted to both atomic absorption and atomic emission was used by Talmi (785)for the determination of zinc and cadmium in environmental samples. A turbulent burner modified with a perforated cap permitted Mashireva et al. (485)and Korovin et al. (395)to report low concentrations of 16 elements in petroleum and its fractions. Nuclear Methods. Larson (415) applied neutron activation (NAA) and emission spectroscopy to the analysis of trace metals in petroleum. He and Tandeski (425)also studied the loss of mercury from sample vials, recommending sealed silica vials instead of polyethylene containers. Al-Shahristani et al. (35)used neutron activation to relate the origin and migration of Iraqi oils by the determination of trace elements present. Berkutova et al. ( 6 4 used the technique to follow the distribution of seven elements in petroleum fractions. Vanadium was determined in both petroleum and cracking catalysts by Passaglia et al. (595). Serebrennikova et al. (735) isolated vanadylporphyrin complexes in western Siberian petroleums and estimated the concentration by NAA. The technique was also used by Umarov and Khasanov (795),and Zaghloul et al. (905) to determine vanadium, sodium, sulfur, and bromine in crude oils. More than 40 elements were analyzed by Kobayashi (385) who studied metal impurities in petroleum products and environmental pollutants. Aluminum and silicon were determined by Kavtanyuk and Umarov (365);oxygen, 256R
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phosphorous, and barium by Vandlik et al. (805);cadmium (205)and 25 trace elements by Filby and Shah (175,195). A californium-252 source was used to determine vanadium by Mancini (465)and Braun (95).It was also used by Orange and Larson (565)to describe a vanadium on-stream analyzer. Emission Techniques. Trace elements in petroleum of marine deposits were determined by spectroscopic analysis of ash samples by Babaev ( 4 4 , while Mashireva and Biktimirova (475) attempted to increase sensitivities for trace analysis by activating carbon electrodes to improve their adsorption capacity. Hearn and Quigley (265)determined the nickel concentration in engine lubricating oils by calibrating with naphthenic acid standards. Woods (885) modified the sample holder for rotating disc electrodes to permit use of a 0.5-mL sample. Modified upper electrodes and evaporation of the sample in a lower electrode enabled Shmulyakovskii et al. (745)to determine trace amounts of copper, lead, and arsenic. Fez03 was used by Nasser (535)as an internal standard in the determination of chromium, manganese, and cobalt in ashes from crude oils. Piepen (605)used argon to stabilize the spark discharge in the analysis of oils by the rotating-disc technique. Ten impurities in crude oils were determined by Farhan and Pazandeh (165) by mixing the sample with graphite and sulfur. The residue after coking was excited by dc arc-and photographed in triplicate. X-ray Fluorescence. Smith et al. (775)employed sulfate ashing, concentration with ion exchange, and internal standard techniques to determine trace iron, nickel, copper, and vanadium by x-ray fluorescence. Detection limits as related to different transmission target tubes were discussed by Zulliger and Stewart (915).Price and Field (625) analyzed for sulfur and lead directly by nondispersive x-ray fluorescence, while Williams (865) discussed various methods employed in the petroleum industry. Miscellaneous. Banerjee et al. ( 5 4 , Gumus (245), and Wilson (875) used spectrophotometric techniques to determine vanadium in petroleum products. Vanadium was also determined by Ratovskaya et al. (645)using an amperometric method; and by Rappeport and Yutkevich (635)using a pyrocatechol technique. Ultraviolet analysis for nickel, vanadium, and chromium were reported by Pasculescu et al. (585). Amalgam polarography was used by Karbainov et al. (335) to detect trace elements in petroleum. Gas chromatography detected iron carbonyl complexes studied by Nametkin et al. (525), and gel chromatography separated porphyrin and nonporphyrin nickel and vanadium compounds as discussed by Sebor et al. (705).Shostakovskii et al. (755) studied different solvents for the extraction of metal porphyrin complexes, while Nuzzi and Casalini (555) used liquid-solid chromatography and pyridine-water extraction to analyze vanadium porphyrins in Venezuelean crude. Vanadyl porphyrins were also separated by Eletskii et al. (155)using anhydrous metallic halogenides. Dickson and Petrakis (125)and Yen (895) used electron spin resonance to characterize the vanadium species in petroleum. Campbell (105)developed a paper test strip for field testing low levels of lead in gasoline. The fluorescence of chloro complexes of lead enabled Weber et al. (855)to determine 0.1 ng lead in lubricating oils. Trace elements in fuels were determined by Carter et al. (115)using spark source and thermal emissions mass spectrometry. Filby (185)discussed the nature of metals in petroleum: porphyrin, nonporphyrin, arsine, and stibine forms. Reviews. Lehmden et al. (435)compared analytical techniques for trace elements in coal, fly ash, fuel oil, and gasoline; Braier and Eppolito ( 8 5 )reviewed instrumental methods for the determination of trace metals in petroleum.
Nonmetal Elements and Compounds W. E. Haines and D. R. Latham Laramie Energy Research Center, Energy Research and Development Administration, Laramie, Wyo. 8207 1
Sulfur. Methods for the determination of total sulfur in oils was the subject of many papers. Combustion methods were
