Hydrocarbons in petroleum

Reforming (Section 2 16) Step in oil refining in which the pro portion of aromatic and branched chain hydrocarbons in petroleum is increased so as to improve the octane rating of gasoline... 

AH Unibon A process for hydrogenating aromatic hydrocarbons in petroleum fractions to form aliphatic hydrocarbons. Developed by UOP. 

Unisar [Union saturation of aromatics] A process for hydrogenating aromatic hydrocarbons in petroleum fractions, using a noble metal heterogeneous catalyst. Developed by the Union Oil Company of California. The first commercial unit opened in Beaumont, TX, in 1969 eight commercial plants were in operation in 1991. 

A species frequently maintains phase equilibrium while it is reacting in one phase. An example is hydrocracking of heavy hydrocarbons in petroleum refining, where H2 from the vapor dissolves into the liquid hydrocarbon phase, where it reacts with large hydrocarbons to crack them into smaller hydrocarbons that have sufficient vapor pressure to evaporate back into the vapor phase. As long as equilibrium of the species between phases is maintained, it is easy to calculate the concentrations in the hquid phase in which reaction occurs. 

Trraidel, J.M. Graff, R. Albrecht, P. Riva, A. (1991) 24,28-Dinor-18a-oleanane, a novel demethylated higher plant derived triterpene hydrocarbon in petroleum. Tetrahedron Lett., 32,2959-62. 

As examples of vapors may be cited those of petroleum hydrocarbons in petroleum refining plants, vapors of solvents (such as alcohol, ether, acetone, carbon tetrachloride, carbon disulfide, etc used in plants manufg expls and propints) vapors of liquid expls (such as DNB, DNT, NG, NGc, DEGDN, etc), and vapors of liquids (such as benzene, toluene or xylene) used as primary materials in the manuf of expls such as TNB, TNT or TNX. Some solid expls such as TNT evolve, when in molten condition, explosive vapors... 

Dr. Anderson. Part of the hydrocarbons in petroleum could have been formed by a Fischer-Tropsch type reaction at say 200°C., at a different place from that in which the petroleum, which contains porphyrins and other thermally labile compounds, is currently found. The broadest interpretation of the similarity between isomers in petroleum and in the Fischer-Tropsch synthesis is that this result suggests that petroleum is produced by radical reactions rather than carbonium ion mechanisms. 

Sachanen, A.N. Hydrocarbons in Petroleum, The Science of Petroleum, v.V, part I, Crude Oils Chemical and Physical Properties, B.T. Brooks and A.E. Dunstan (eds.), Oxford University Press, London (1950). 

Matisova and co-workers11 have suggested that the need for a reproducible sample volume can be eliminated by combining the standard addition method with an in situ internal standard method. In the quantitative analysis of hydrocarbons in petroleum, they chose ethyl benzene as the standard for addition, but they used an unknown neighboring peak as an internal standard to which they referenced their data. This procedure eliminated the dependency on sample size and provided better quantitation than the area normalization method they were using. 

Rothermich, M. M., Hayes, L. A. Lovley, D. R. (2002). Anaerobic, sulfate-dependent degradation of polycyclic aromatic hydrocarbons in petroleum-contaminated harbor sediment. Environmental Science and Technology, 36, 4811-17. 

Further work on the free and ester-bound triterpenoid alcohols in cellular subtractions of Calendula officinalis flowers has appeared. An investigation of the mass spectral fragmentation of pentacyclic hydrocarbons in petroleum has been published. ... 

Hoering T. C. (1981) Monomethyl acyclic hydrocarbons in petroleum and rock extracts. Carnegie Inst. Wash. Yearb. 80, 389-393. 

Mango F. D. (1990) The origin of light hydrocarbons in petroleum a kinetic test of the steady-state catalytic hypothesis. Geochim. Cosmochim. Acta 54, 1315-1323. 

Moldowan J. M. and Fago F. J. (1986) Structure and significance of a novel rearranged monoaromatic steroid hydrocarbon in petroleum. Geochim. Cosmochim. Acta 50, 343—351. 

Moldowan J. M. and Seifert W. K. (1979) Head-to-head Unked isoprenoid hydrocarbons in petroleum. Science 204, 169-171. 

Noble R. A., Alexander R., and Kagi R. I. (1986) Identification of some diterpenoid hydrocarbons in petroleum. Org. 

Gieg L. M. and Suflita J. M. (2002) Detection of anaerobic metabolites of saturated and aromatic hydrocarbons in petroleum-contaminated aquifers. Environ. Sci Technol 36(17), 3755-3762. 

Methane from Carbides.—Another method of preparation is of interest and importance because of its connection with theories as to the formation of methane and other hydrocarbons in petroleum. With some metals carbon forms compounds which are very stable at high temperatures, and which have been artificially produced in the electric furnace (about 35O0°C.) by Moissan. These metallic carbon compounds, known as carbides, are, most of them, easily decomposed by water at ordinary temperatures, and when so decomposed they yield various members of the hydrocarbon group of compounds. A familiar example of this class of reactions is the one by which acetylene gas is made by the action of water on calcium carbide. The carbide of aluminium decomposes with water and yields methane according to the foUowing reaction ... 

For example, hydrocarbons react with oxygen at high temperatures to form (primarily) carbon dioxide and water vapor. Oxidation that takes place very rapidly, usually at high temperatures, is known as combustion. The combustion of hydrocarbons in petroleum and natural gas has been another major source of energy in human civilization over the past 200 years. 

Williams, R. B. (1958). Characterization of hydrocarbons in petroleum by nuclear magnetic resonance spectrometry. Am. Soc. Test. Mater. Spec. Puhl., 1958 (224), 168-194. 

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