Petroleum Components Research Articles

Phase-controlled molecular fractionations in migrating petroleum charges

Abstract An experimental approach has been used to make a preliminary examination of the possible effects of partitioning processes distributing molecular markers between vapour and liquid petroleum phases during petroleum migration in the system gas-saturated oil/condensate-saturated gas. These effects are discussed with reference to several traditional petroleum geochemical parameters. Some source and maturity related geochemical parameters are dispersed from the inherited source values when a petroleum system undergoes a transition from a single phase gas-condensate to a two phase system and it is probable that partitioning is one of the many processes that contribute to the scattered data sets observed in natural systems particularly those associated with gas/condensates. In addition to affecting gross composition and gas and gasoline range composition, physical partitioning of petroleum components between vapour and liquid phases in deep reservoirs containing rich gas condensate vapour and a liquid petroleum phase in equilibrium can affect even high molecular weight components, selectively partitioning lower homologues into the vapour phase. This may disperse to various degrees any source inherited signature in source facies or maturity interpreted from parameters such as aromatic hydrocarbon distribution, gasoline range parameters, or sterane carbon number distribution. Migration history, or the frequency and extent of multiple equilibrations between vapour and liquid phases in deep high pressure reservoirs followed by selective release of one phase to a shallower position to produce a two phase petroleum system is proposed as an important variable in the geochemical interpretation of once equilibrated petroleum systems. It is concluded that phase related effects must be considered in addition to accepted source and maturity considerations as controlling the molecular composition of two-phase petroleums derived from single-phase precursors. This is particularly so for rich gas condensate systems.

An assessment of terrestrial higher molecular weight lipid compounds in aerosol particulate matter over the south atlantic from about 30–70°S

A cruise in the South Atlantic allowed the acquisition of a series of aerosol particle samples (high volume filtering) from Rio de Janeiro (Brazil) south to the Antarctic (Bransfield Strait) and back toward Punta Arenas (Chile). These samples were analyzed for the content and composition of solvent-soluble organic matter (range 55–5670 ng/m 3) for a preliminary evaluation of the terrestrial components of this organic matter. Distributions of n -alkanes, n -alkanoic acids and n -alkanols were determined (gas chromatography/mass spectrometry) and compared with analogous information on biological and geological (e.g. petroleum) sources. A preliminary data correlation was also attempted by collection of composited local vegetation wax in one possible aerosol particle source region. The results show a petroleum derived component (unresolved hydrocarbon mixture and n -alkanes with no carbon number predominance) in most samples, notably evident remote from continental areas where the plant wax signature (straight-chain homologs C 20) was less concentrated, as contrasted with the marine/microbial input (compounds < C 20). A procedure for subtraction of the petroleum component in n -alkane traces, as well as analyses of oxygenated components, permitted resolution of some ambiguities and highlighted the biological fingerprint in all cases. In aerosols close to land, polycyclic biomarkers, indicative of fossil fuel (e.g. 17α(H)-hopanes, etc.) and/or biological input (e.g. cholesterol, etc.) could be recognized. Natural product biomarkers of terrestrial vegetation (e.g. amyrins, oleanolic and ursolic acids) showed a rapid depletion downwind from their source regions.

A simple, rapid and simultaneous analysis of complex volatile hydrocarbon mixtures in blood using gas chromatography/mass spectrometry with a wide-bore capillary column

A screening method for detecting volatile hydrocarbons in blood has been developed using gas chromatography/mass spectrometry with a wide-bore capillary column and a headspace method. Toluene-d8 and indan were used as the internal standards for quantitative analysis. Hydrocarbons with retention indices from 600 to 1200 were simultaneously and quantitatively detected in relatively low concentrations (0.01 microgram/ml) in reconstructed ion chromatography. This method could prove useful in forensic cases in which urgent examination of complex hydrocarbon mixtures, e.g. petroleum components, is required.

Relationships governing the distribution of vanadium, nickel and their porphyrin complexes in petroleum components

Relationships governing the distribution of vanadium, nickel and their porphyrin complexes in petroleum components

The use of silicalite for rapid isolation of branched and cyclic alkane fractions of petroleum

In this note we describe a procedure using silicalite sorption for rapidly and conveniently isolating a branched and cyclic fraction of a petroleum suitable for analysis of saturated biomarker components by GC-MS. By examination of m/z 191, 217, 218 and 259 mass chromatograms of silicalite-included fractions, and comparison of 5 Å excluded fractions with silicalite-excluded fractions, we have rigorously established that this method is valid for analysis of sterane and hopane biomarker components of petroleum. The method makes possible a one-day turnaround for routine biomarker analysis.

Dissolved petroleum residues and alkylbenzene photo-oxidation products in the upper arabian gulf

Lipophilic dissolved material was concentrated by in-situ liquid-solid adsorption on Amberlite XAD-2 resin from glass-fibre-filtered coastal seawater in the upper Arabian Gulf in the fall of 1986. 10% aqueous acetone was used for countercurrent desorption under reflux. In the concentrated eluate petroleum components were characterized and quantified by GC-MS as were ketonic photo-oxidation products of alkylbenzenes. Concentrations of the latter exceeded those of unaltered petroleum components by roughly a factor of 10.

ENVIRONMENTAL EFFECTS OF THE PAC BARONESS OIL AND COPPER SPILL

ABSTRACT A study was conducted to investigate the initial environmental effects of an offshore oil and copper spill resulting from the sinking of the freighter Pac Baroness approximately 19 kilometers (km) southwest of Point Conception, California, at a water depth of 430 meters (m). Gas chromatography with mass spectrometry detection (GC/MS) was used to examine the distribution and levels of hydrocarbons in surficial sediments and to compare patterns of hydrocarbons in the sediments to those of a source-oil sample obtained from the vessel. Potential impacts of the spill on macroinfauna were also evaluated by examining changes in community structure and composition and in abundances of component species, based on comparison between control and wreck-site samples. Results of the chemical analyses show that sediment samples collected in the vicinity of the Pac Baroness contain elevated levels of hydrocarbons and other petroleum components that clearly originate from the oil on board the sunken vessel. Statistical comparisons of the macroinfaunal data reveal distinct biological effects of the spill within the immediate surrounding area of the vessel, at water depths of 410 to 436 m. Among these effects are significant reductions in mean number of species, mean number of individuals (all species combined), abundances of several component species (half of which are dominants within the community), and the combined abundance of sensitive amphipod species. These initial levels of contamination and associated environmental effects are unique in consideration of the extreme water depth in which the spill occurred.

Influence of the nature of the precipitator on the composition of the high-molecular petroleum components isolated

Influence of the nature of the precipitator on the composition of the high-molecular petroleum components isolated

Benzene.

Benzene is used as an additive to gasoline to increase the octane and as a chemical intermediate in the synthesis of such compounds as styrene, synthetic rubber, phenol, alkylarnesulfonate detergent, nitrobenzene (aniline), and cyclohexane. The properties of benzene are shown in Table 1.Benzene is produced at low levels in a number of biologic processes and is a component of petroleum (USEPA 1983a). Benzene is produced in large amounts, e.g., 9 billion lbs (4.08 billion kg) in 1981 (USITC 1984), and is used largely as a feedstock in the production of other chemicals. Small amounts of benzene have been used as a solvent, but this use has been discontinued. Benzene also is produced indirectly in large volumes, such as during the refining of gasoline and other operations. The average benzene content of gasoline is less than 1% (Run-ion 1975).KeywordsHealth AdvisoryOdor ThresholdBenzene VaporBenzene ExposureChemical Abstract ServiceThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Biomarkers: Molecular Fossils

Curiosity about the history of life on our planet is a major motivational force for earth scientists. Fossil organic compounds, the components of petroleum and sedimentary organic matter, record aspects of the evolution of the biosphere from as far back as 1.8 billion years and perhaps longer. Elucidation of this record is continually advancing as a result of the concerted interests and efforts of geologists, biologists and chemists. It is also aided by advances in technique and instrumentation. Fascinating new developments and insights abound. In this paper I review some early landmarks and discuss the recent progress made in organic geochemistry, particularly as it applies to biomarker research. The examples of recent work are heavily biased toward my own interests and are not intended to be comprehensive. Because the literature citations are also selective and rely heavily on reviews, readers are advised to seek out the primary literature for accurate detail of specific subjects.

Hydrocarbons and Complaints About Fish Quality in the Mackenzie River, Northwest Territories, Canada

Abstract The Mackenzie River in northwestern Canada is the largest North American source of freshwater to the Arctic Ocean There are continuous discharges of petroleum into the river from an oil field at Norman Wells both from refinery and natural seepage sources. Recently oil production was expanded using several artificial islands constructed in the river Coincident with the expansion native DENE fishermen in downstream communities complained that the quality of fish deteriorated. Specifically, the liver of burbot (Lota lota) was reported to have become small and dark in colour, and our investigation of that complaint is the subject of this report. Examination of the burbot revealed that the liver condition was associated with a low content of fat The question posed was whether this quality problem could be related to petroleum inputs from Norman Wells. Residue analyses of the fish showed low, but consistent, contamination with low-boiling aromatic hydrocarbons, with fish taken in winter more highly contaminated than fish taken in summer. The low levels in summer fish were found in fish from many freshwater locations with no obvious connection to a petroleum source This may reflect a broad atmospheric dispersal of these materials. Burbot from the lower Mackenzie River did not have elevated liver mixed-function oxidase enzyme activities relative to a reference population from Lake Winnipeg Experimental treatments with oil induced these enzyme activities, and so fish seem unlikely to have been affected by the enzyme inducing components of petroleum. Experimental starvation of burbot in the laboratory resulted in a loss of liver fats and in development of apparently the same liver condition The condition of the fish seems more likely to be of natural origin through factors related to nutrition or parasitism, although pollution cannot be ruled out definitively. Unexpectedly high concentrations of toxaphene (up to 5000 ng/g wet weight) and other organochlorines were found in burbot livers

Role of the Engineer in the Petroleum E&amp;P Industry in the Year 2000

Summary This paper examines the role of engineers in major oil companies during the period from 1986 to 2000. It looks at both the majors involvement in petroleum E&amp;P and the significant technical challenges facing the industry for the remainder of the 20th century. The paper forecasts the functions of the engineer during this period, the computer support available to the engineer in the year 2000, and the qualifications required of the entry-level engineer in 2000. Introduction At the request of the SPE Education and Professionalism Committee, this paper addresses the five following questions.What aspects of the petroleum industry will major oil companies primarily be concerned with in the year 2000?What will be the significant technical problems addressed by the petroleum industry during the remainder of this century?What support will computers provide the engineer in the year 2000, and how should the engineer be prepared to use this technology effectively?How will the functions of engineers change during the remainder of this century?What will be the qualifications required for an entry-level engineering position in the petroleum industry in the year 2000? This paper does not and cannot predict the future price of oil, the estimated number of active drilling rigs, the job opportunities available for engineers in the petroleurn E&amp;P industry, or any of the other standard measures of economic vitality. To do so would require an infallible econometric model, inerrant data about parameters going into the model, and above all, incredible prescience about future political developments worldwide. This paper is based on certain premises, however, which are summarized in Table 1. Major Oil Companies' Involvement in Petroleum E&amp;P In the petroleum E&amp;P or "upstream" business, major companies can be characterized as being more or less self-sustaining in their technical work. In exploration, their own employees do the geology and geophysics; in development and production, they do their own engineering and operations; in both, they are supported by their own research effort. Major oil companies are defined here as the top 16 oil companies, based on worldwide liquid reserves, of the 1984 OGJ 400.1 This grouping was used because of data accessibility. Thus major components of the worldwide petroleum E&amp;P industry---e.g., British Petroleum, Royal Dutch/Shell Group, various national oil companies, and eastern European organizations---are not included in this analysis. Today major oil companies account for 4.7% of the world's liquid petroleum reserves, 4.3% of the gas reserves, and 16% of the liquids production (see Table 2). In the U.S., they drill about 15% of both the exploration wildcat wells and development wells, and probably do a somewhat larger percentage of the geologic and geophysical effort that supports this drilling. Whether these relative percentages will increase or decrease by the year 2000 is basically an economic/political question and beyond the scope of this paper. When considered on a global basis, the major oil companies will operate at a high-intensity level in the year 2000 in all four of the classic E&amp;P functions: exploration, development, production, and EOR. In the U.S. only, the exploration and development functions probably will be at a moderate activity level because the U.S. will be well advanced in the so-called E&amp;P cycle, with a smaller number of exploration and development opportunities available. These relative activity levels are summarized in Table 3. Significant Technical Challenges for the Remaining 20th Century To consider the technical challenges facing the petroleum industry during the remainder of this century, we return to the major E&amp;P functions of development, production, etc. Development. Table 4 summarizes the future problems and challenges of the development function. The two major challenges in developing oil and gas reserves will be an early, accurate characterization of the reservoir and optimal engineering design in drilling and completing the wells. Development. Table 4 summarizes the future problems and challenges of the development function. The two major challenges in developing oil and gas reserves will be an early, accurate characterization of the reservoir and optimal engineering design in drilling and completing the wells.

Catagenesis and composition of petroleum: Origin of n-alkanes and isoalkanes in petroleum crudes

Distribution of n-alkanes and isoalkanes in ca. 50 petroleum crudes have been examined by the gas chromatography. Molar distributions of n-alkanes with respect to their c atom numbers in the majority of crudes follow the exponential law, which signifies a random, chemical nature of n-alkane-generating processes occurring in the catagenesis stage of petroleum maturation. Similar distributions of n-alkanes were found in the products of mild thermolysis of heavy n-alkanes. Isoalkanes represent a major, 10–25%, petroleum component. The principal types of isoalkanes in crudes are monomethyl-branched, with the branches randomly positioned in the chains, and dimethyl-branched with one of the methyl groups predominantly in the second position in the chains. Thermolysis studies of individual n-alkanes, alkanoic acids, and esters in the presence of various minerals provided an explanation of the n-alkane and isoalkane distributions. Selected heavy n-alkanes are initially formed in decarboxylation reactions of heavy n-alkanoic acids and esters. Extensive thermocracking produces mixtures of lighter n-alkane and α-olefins. The olefins, in the presence of acidic clays, are converted in cationic reactions into mixtures of predominantly mono- and dimethyl-branched isoalkanes.

Contamination Pétrolière de la Microcouche de Surface du Golfe de Fos-sur-mer (Mer Méditerranéee)

Abstract In a general study on the petroleum contamination of the Fos-sur-mer Gulf (Mediterranean Sea), the surface microlayer was sampled. We present here the first results reported up to date in this area, based on a sampling carried out with a rotating PVC drum at 3 stations in May 1985. Very high hydrocarbons concentrations were sometimes observed in the surface film, which appears more heterogeneous than the underlaying water column (0.5-2m). Water samples were filtered through fiberglass filters (0.5-1 μm). Both dissolved and particulate phases were separately extracted and analysed, providing evidence that suspended particles are the major vector for the accumulation and the transport of petroleum pollutants in these neritic waters. The petroleum origin of “total hydrocarbons” fractions is confirmed by GC and HPLC which reveal characteristic features for n-alkanes and polynuclear aromatic hydrocarbons. HPLC analysis of polar (non-hydrocarbons) fractions could indicate their formation from petroleum components. Furthermore, the comparison with the underlying waters shows that volatilization and biodegradation are the major processes affecting hydrocarbons distribution in these superficial waters. Biological data (bacteria, chlorophylls, ATP and energetic charge) were simultaneously measured and indicated an important inhibition of phyto- and bacterio- neuston regarding to the planktonic organisms.

Quantitative alteration of readily volatile petroleum components in water pollution by simulated weather factors and a rapid column chromatographic separation of the aromatic petroleum fraction

It is demonstrated by simulated environmental factors that after the application of petroleum onto a water surface, alterations in the distribution pattern are primarily caused by evaporation. During 8 h of analysis, it has been shown that evident loss by evaporation occurs especially for low-molecular n-alkanes, where the evaporating velocity is dependent on the film thickness, water temperature and wind velocity. Quantitatively, the concentration decrease of n-alkanes, nonane to pentadecane as well as pristane was determined by capillary gas chromatography with flame ionization detection at different periods of time, different water temperature and film thickness.

Genesis and Synthesis of Petroleum Hydrocarbons

Abstract Based on observation of the clay-catalyzed conversion of the fermentation products of glucose to hydrocarbons and the related evidence from the literature, glucose is recognized as the primary precursor of petroleum. A multiple pathway of petroleum formation is presented. In aerobic growth of living cells, fatty acids and related products are generated from glucose which are buried and incorporated into kerogen during diagenesis, and finally converted to petroleum through catagenesis. By anaerobic fermentation, glucose may be converted into simple oxygenates which can be transformed into components of petroleum upon catalysis by clay. In-depth analysis of the chemistry involved suggested that a sequence of four basic chemical reactions, oxygen shift, decarboxylation, dehydration, and polymerization, is sufficient to effect the transition from glucose to hydrocarbons. Synthesis of petroleum hydrocarbons by existing industrial processes, namely fermentation and catalysis, appears to be feasible. Pe...

Polarographic behaviour of petroleum components in aqueous solutions: A study using DPP and convective adsorption accumulation

Tensametric behaviour of solutions of petroleum and its fractions in aqueous base electrolytes was studied by differential pulse polarographic method (DPP) using a stationary mercury drop electrode with adsorptive accumulation. The results indicate that water pollution with petroleum can be determined by DPP, the sensitivity of the determination depending on the quality of the pollutant and on the composition of the base electrolyte. Well utilizable calibration curves were obtained with Diesel oil at concentrations from 30-50 μl/l to 0.5 mg/l and with Saratov petroleum from 0.1-0.2 mg/l to 3.3 mg/l. Use of adsorptive accumulation led to a marked increase of the sensitivity of the analysis.

Polarographic behaviour of petroleum components in aqueous solutions: Application of electrocapillary measurements and convective adsorption accumulation

Electrocapillary investigations by the drop time method revealed a rather strong surface activity of aqueous petroleum solutions and some petroleum fractions in solutions of base electrolytes at the dropping mercury electrode, depending on the quality of the surfactant. The highest surface activity and sensitivity of analytical determination was found between -0.4 and -0.6 V (S.C.E.). The detection limit of the electrocapillary method was 10-20 μg/l for Diesel oil and up to 5 times higher for petroleum samples. The sensitivity of the measurements at lowest concentrations was increased by convective adsorption accumulation at the surface of the growing drop.

Laser spectrochromatographic analysis of petroleum components

A system combining a gas chromatograph and a laser optoacoustic spectrometer (with a CO2 laser and means for fast frequency scanning) was used to investigate model hydrocarbon mixtures, as well as some real objects in the form of benzine fractions of petroleum oil. The fast scanning regime was used to record optoacoustic spectra of hydrocarbons (in the range 9.2–10.8μ) during the travel time (1–10 sec) of the individual components of a mixture through an optoacoustic cell in the course of chromatrographic separation of these components. The spectra were used to carry out a group hydrocarbon analysis of benzine fractions of petroleum oil from various locations. The proposed method was relatively fast and was characterized by a good ability for identification of various components, compared with the usually employed method such as gas–liquid capillary chromatography.

Composition and structure of high molar mass polycyclic naphthenic hydrocarbons of petroleum

Studies of high MW hydrocarbons and other petroleum components are scientifically significant and of considerable practical value in view of the problem of processing heavy petroleums and petroleum residues. Studies of the chemical composition of the higher molecular weight hydrocarbon and heterocyclic components of petroleum in such stocks demand efficient methods for differentiating the complex multi-component mixtures that they contain. An investigation of the polycyclic naphthenes isolated from West Turkmenistan petroleums (Koturdepe and Oval-Toval) is reported here. Petroleums from these deposits, and their high-boiling distillates have a high content (above 73%) of saturated paraffin-naphthene hydrocarbons.