Journal articles: 'Aliphatic and aromatic hydrocarbons'

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Doley, Ruby, and Manoj Barthakur. "Biotransformation of aromatic hydrocarbon: Naphthalene to Aliphatic Hydrocarbons through Staphylococcus pasteuri RD2." Annals of Plant Sciences 7, no. 5 (April 30, 2018): 2247. http://dx.doi.org/10.21746/aps.2018.7.5.7.

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Aromatic hydrocarbons like naphthalene are common environmental pollutants of petrochemical waste. Microorganisms have been exploited since long back to clean up such pollutants by converting them in to either non- toxic or less toxic aromatic or aliphatic compounds. A bacterial strain have been isolated from oil sludge of Guwahati Refinery, Assam and was identified as Staphylococcus pasteuri RD2 (NCBI accession number MG680735) through 16srDNA sequence analysis and molecular phylogeny. The bacterial strain transforms Naphthalene, a common hazardous aromatic hydrocarbon found in petrochemical waste, into a number of less hazardous aliphatic hydrocarbons. Detection of compounds such as Decane, Dodecane, tetradecane, Hexadecane, Eicosane, and heptane by GC-MS analysis of naphthalene enrichment culture broth suggested that the bacterial strain was able to transform naphthalene in to different aliphatic hydrocarbons with less toxicity and having chain length of C7 to C20. It has also been depicted a pathway to obtain aliphatic hydrocarbons with higher caloric value from aromatic hydrocarbon waste.

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Díaz-Ramírez, I. J., H. Ramírez-Saad, M. Gutiérrez-Rojas, and E. Favela-Torres. "Biodegradation of Maya crude oil fractions by bacterial strains and a defined mixed culture isolated from Cyperus laxus rhizosphere soil in a contaminated site." Canadian Journal of Microbiology 49, no. 12 (December 1, 2003): 755–61. http://dx.doi.org/10.1139/w03-098.

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Ten bacterial strains were isolated by enrichment culture, using as carbon sources either aliphatics or an aromatic–polar mixture. Oxygen uptake rate was used as a criterion to determine culture transfer timing at each enrichment stage. Biodegradation of aliphatics (10 000 mg L–1) and an aromatic–polar mixture (5000 mg L–1, 2:1) was evaluated for each of the bacterial strains and for a defined culture made up with a standardized mixture of the isolated strains. Degradation of total hydrocarbons (10 000 mg L–1) was also determined for the defined mixed culture. Five bacterial strains were able to degrade more than 50% of the aliphatic fraction. The most extensive biodegradation (74%) was obtained with strain Bs 9A, while strains Ps 2AP and UAM 10AP were able to degrade up to 15% of the aromatic–polar mixture. The defined mixed culture degraded 47% of the aliphatics and 6% of the aromatic–polar mixture. The defined mixed culture was able to degrade about 40% of the aliphatic fraction and 26% of the aromatic fraction when grown in the presence of total hydrocarbons, while these microorganisms did not consume the polar hydrocarbons fraction. The proposed strategy that combines enrichment culture together with oxygen uptake rate allowed the isolation of bacterial strains that are able to degrade specific hydrocarbons fractions at high consumption rates.Key words: biodegradation, defined mixed culture, enrichment culture, hydrocarbon fractions, oxygen uptake.

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Sloan, G. C. "Spitzer spectroscopy of unusual hydrocarbons in cool radiative environments." Proceedings of the International Astronomical Union 4, S251 (February 2008): 191–94. http://dx.doi.org/10.1017/s1743921308021534.

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AbstractThe Spitzer Space Telescope has discovered several objects with unusual spectra, where the emission features from polycyclic aromatic hydrocarbons (PAHs) are shifted to longer wavelengths than normally observed. Previously, only two of these class C PAH spectra had been identified. The new and larger sample reveals that PAHs emit at longer wavelengths when processed by cooler radiation fields. Limited laboratory data show that samples with mixtures of aromatic and aliphatic hydrocarbons produce emission features at longer wavelengths than purely aromatic samples. The aliphatic bonds are more fragile and would only survive in cooler radiation fields. In harsher radiation fields, the aliphatics attached to the aromatic hydrocarbons are destroyed.

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April, T. M., J. M. Foght, and R. S. Currah. "Hydrocarbon-degrading filamentous fungi isolated from flare pit soils in northern and western Canada." Canadian Journal of Microbiology 46, no. 1 (December 17, 1999): 38–49. http://dx.doi.org/10.1139/w99-117.

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Sixty-four species of filamentous fungi from five flare pits in northern and western Canada were tested for their ability to degrade crude oil using gas chromatographic analysis of residual hydrocarbons following incubation. Nine isolates were tested further using radiorespirometry to determine the extent of mineralization of model radiolabelled aliphatic and aromatic hydrocarbons dissolved in crude oil. Hydrocarbon biodegradation capability was observed in species representing six orders of the Ascomycota. Gas chromatography indicated that species capable of hydrocarbon degradation attacked compounds within the aliphatic fraction of crude oil, n-C12- n-C26; degradation of compounds within the aromatic fraction was not observed. Radiorespirometry, using n-[1-14C]hexadecane and [9-14C]phenanthrene, confirmed the gas chromatographic results and verified that aliphatic compounds were being mineralized, not simply transformed to intermediate metabolites. This study shows that filamentous fungi may play an integral role in the in situ biodegradation of aliphatic pollutants in flare pit soils.Key words: bioremediation, filamentous fungi, flare pits, hydrocarbon degradation, petroleum.

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Feitkenhauer, H., and H. Märkl. "Biodegradation of aliphatic and aromatic hydrocarbons at high temperatures." Water Science and Technology 47, no. 10 (May 1, 2003): 123–30. http://dx.doi.org/10.2166/wst.2003.0555.

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In this paper, the high temperature (65-75°C) biodegradation of aliphatic and aromatic hydrocarbons is investigated and kinetic parameters are derived. The shift of the physico-chemical system properties with rising temperature will be discussed in detail. For example, the solubility of naphthalene is increased by a factor of about ten if the temperature is increased from 20 to 75°C. This effect is essential to increase the bioavailability of sparingly soluble hydrocarbons. It is also demonstrated in experiments that very high oxygen transfer rates can be obtained at high temperatures in the presence of hydrocarbons. It is shown that efficient phenol biodegradation is essential for high temperature hydrocarbon degradation because some microorganisms tend to transform phenols into polyphenols which are very inhibitory for microbial growth. A defined mixed culture adapted to phenol converted more than 90% of a mixture of phenol, hexadecane and pyrene and a very high maximal growth rate of 0.19 h−1 was determined. A yield coefficient YX/S of about 0.8 g (biomass)/g (hydrocarbons) was calculated in this experiment. In a separate experiment the influence of the hydrocarbon droplet size on the biodegradation is investigated at 70°C using a newly isolated Thermus sp. In this case, the growth on a hexadecane/pyrene mixture was described by a model based on the Monod equation and the corresponding kinetic parameters are derived. A mixed culture was used for the bioremediation of soil in a slurry reactor. The initial contamination of 11 g/kg was lowered to about 2 g in a reactor inoculated by an immobilized culture of extreme thermophilic microorganisms, while 9 g/kg remained in a sterile control.

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Parinos, C., A. Gogou, I. Bouloubassi, R. Pedrosa-Pàmies, I. Hatzianestis, A. Sanchez-Vidal, G. Rousakis, D. Velaoras, G. Krokos, and V. Lykousis. "Occurrence, sources and transport pathways of natural and anthropogenic hydrocarbons in deep-sea sediments of the eastern Mediterranean Sea." Biogeosciences 10, no. 9 (September 24, 2013): 6069–89. http://dx.doi.org/10.5194/bg-10-6069-2013.

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Abstract. Surface sediments collected from deep basins (1018–4087 m depth) of the eastern Mediterranean Sea (Ionian Sea, southern Aegean Sea and northwestern Levantine Sea) were analyzed for aliphatic and polycyclic aromatic hydrocarbons as tracers of natural and anthropogenic inputs. Concentrations of total aliphatic hydrocarbons, n-alkanes and the unresolved complex mixture (UCM) of aliphatic hydrocarbons varied significantly, ranging from 1.34 to 49.2 μg g−1, 145 to 4810 ng g−1 and 0.73 to 36.7 μg g−1, respectively, while concentrations of total polycyclic aromatic hydrocarbons (PAHs) ranged between 11.6 and 223 ng g−1. Molecular profiles of determined hydrocarbons reflect a mixed contribution from both natural and anthropogenic sources in deep-sea sediments of the eastern Mediterranean Sea, i.e., terrestrial plant waxes, degraded petroleum products, unburned fossil fuels and combustion of grass, wood and coal. Hydrocarbon mixtures display significant variability amongst sub-regions, reflecting differences in the relative importance of inputs from various sources and phase associations/transport pathways of individual hydrocarbons that impact on their overall distribution and fate. Hydrocarbon concentrations correlated significantly with the organic carbon content of sediments, indicating that the latter exerts an important control on their transport and ultimate accumulation in deep basins. Additionally, water masses' circulation characteristics also seem to influence the regional features and distribution patterns of hydrocarbons. Our findings highlight the role of deep basins/canyons as repositories of both natural and anthropogenic chemical species.

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Schuhmann, M., K. Altwegg, H. Balsiger, J. J. Berthelier, J. De Keyser, B. Fiethe, S. A. Fuselier, et al. "Aliphatic and aromatic hydrocarbons in comet 67P/Churyumov-Gerasimenko seen by ROSINA." Astronomy & Astrophysics 630 (September 20, 2019): A31. http://dx.doi.org/10.1051/0004-6361/201834666.

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Context. Unlike all previous cometary space missions, the Rosetta spacecraft accompanied its target, comet 67P/Churyumov-Gerasimenko, for more than two years on its way around the Sun. Thereby, an unexpected diversity and complexity of the chemical composition was revealed. Aims. Our first step of decrypting the exact chemical composition of the gaseous phase is the identifying and quantifying the bulk composition of the pure aromatic and aliphatic hydrocarbons. Methods. For this study, data from ROSINA–Double Focusing Mass Spectrometer (DFMS) onboard the Rosetta spacecraft and the laboratory twin model were used. A joint campaign of laboratory calibration measurements and space data analysis was performed to derive the hydrocarbon bulk composition for the post-inbound equinox period at 1.52 AU in May 2015. Furthermore, several other mission phases were investigated to determine the dependencies of season, location, and heliocentric distance on the relative abundances of hydrocarbons. Results. It is shown that the bulk composition of the gaseous phase includes a high number of aliphatic compounds such as methane, ethane, and propane, as well as the aromatic compounds benzene and toluene. Butane and pentane were successfully identified in measurements at closer distance to the comet in May 2016. Furthermore, the presence of hexane and heptane in the coma is confirmed on rare occasions during the mission. Their presence in DFMS space data appears to be linked to days or periods of high dust activity. In addition to the saturated aliphatic and aromatic compounds, a high number of remaining unsaturated species is present, which cannot be explained by fragmentation of saturated species or contribution from other organic molecules in addition to pure hydrocarbons. This indicates the existence of unsaturated aliphatic and aromatic hydrocarbon molecules in the coma of comet 67P.

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Asaftei, Iuliean V., Ion Sandu, Nicolae Bilba, Neculai Catalin Lungu, Maria Ignat, and Elvira Mahu. "Oligo-Aromatization of Light Hydrocarbons from Petroleum Refining Processes Over ZnO/MFI Microporous Material." Revista de Chimie 71, no. 2 (March 3, 2020): 403–12. http://dx.doi.org/10.37358/rc.20.2.7943.

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The conversion of light hydrocarbons resulted as by-product of petroleum refining (mixtures of (n + i) butanes, 52.28 � 63.20 vol.%, (1-, cis-, trans-, 2-) butenes, 28.64 � 36.43 vol.% and propane � propylene, 4.79 � 14.64 vol.%) over bifunctional 5% ZnO/HZSM-5 co-catalyst in a fixed-bed stainless-steel reactor (Twin Reactor System Naky) at 450�C, 4 atm. total pressure and at a space velocity (WHSV) of 1 h-1 have been investigated. The results indicate that the selectivity to light aromatics � benzene, toluene and xylenes (BTX) � and to both the gaseous C1, C2 - C4 hydrocarbons and liquid (i + n) C5 � C10 aliphatic hydrocarbons depends on the time on stream of the process. This is a result of coke deposition (polyunsaturated compounds) and catalyst deactivation. The aromatics BTX represent 59-60 wt% in the liquid product during the first 24-36 hours time-on-stream and only 20-30 wt% after 40 hours of reaction when the aliphatic hydrocarbon C5 � C10 (mostly iso) and ]C10 (denoted �oligo�) reach to 70 � 80 wt%. The aromatic products were principally toluene, xylenes and benzene, theirs concentration varying with the time on stream of the process. The initial aromatization process described as dehydrocyclodimerization of alkanes and alkenes, principally to aromatics BTX and molecular hydrogen is accompanied by an oligomerization, isomerisation, cracking and alkylation process to form finally in the liquid product an excessively mixture of iso- and normal- C5 � C10 aliphatic hydrocarbons and ] C10.

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Firrincieli, Andrea, Andrea Negroni, Giulio Zanaroli, and Martina Cappelletti. "Unraveling the Metabolic Potential of Asgardarchaeota in a Sediment from the Mediterranean Hydrocarbon-Contaminated Water Basin Mar Piccolo (Taranto, Italy)." Microorganisms 9, no. 4 (April 16, 2021): 859. http://dx.doi.org/10.3390/microorganisms9040859.

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Increasing number of metagenome sequencing studies have proposed a central metabolic role of still understudied Archaeal members in natural and artificial ecosystems. However, their role in hydrocarbon cycling, particularly in the anaerobic biodegradation of aliphatic and aromatic hydrocarbons, is still mostly unknown in both marine and terrestrial environments. In this work, we focused our study on the metagenomic characterization of the archaeal community inhabiting the Mar Piccolo (Taranto, Italy, central Mediterranean) sediments heavily contaminated by petroleum hydrocarbons and polychlorinated biphenyls (PCB). Among metagenomic bins reconstructed from Mar Piccolo microbial community, we have identified members of the Asgardarchaeota superphylum that has been recently proposed to play a central role in hydrocarbon cycling in natural ecosystems under anoxic conditions. In particular, we found members affiliated with Thorarchaeota, Heimdallarchaeota, and Lokiarchaeota phyla and analyzed their genomic potential involved in central metabolism and hydrocarbon biodegradation. Metabolic prediction based on metagenomic analysis identified the malonyl-CoA and benzoyl-CoA routes as the pathways involved in aliphatic and aromatic biodegradation in these Asgardarchaeota members. This is the first study to give insight into the archaeal community functionality and connection to hydrocarbon degradation in marine sediment historically contaminated by hydrocarbons.

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10

Parinos, C., A. Gogou, I. Bouloubassi, R. Pedrosa-Pàmies, I. Hatzianestis, A. Sànchez-Vidal, G. Rousakis, D. Velaoras, G. Krokos, and V. Lykousis. "Occurrence, sources and transport pathways of natural and anthropogenic hydrocarbons in deep-sea sediments of the Eastern Mediterranean Sea." Biogeosciences Discussions 9, no. 12 (December 13, 2012): 17999–8038. http://dx.doi.org/10.5194/bgd-9-17999-2012.

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Abstract. Surface sediments collected from deep basins (22 stations, 1018–4087 m depth) of the Eastern Mediterranean Sea (EMS) were analyzed for aliphatic, triterpenoid and polycyclic aromatic hydrocarbons (PAHs) as tracers of natural and anthropogenic inputs. Concentrations of total aliphatic hydrocarbons (TAHC), n-alkanes (NA) and the Unresolved Complex Mixture (UCM) of aliphatic hydrocarbons ranged from 1.34 to 49.2 µg g−1, 145 to 4810 ng g−1 and 0.73 to 36.7 µg g−1, respectively, while total PAHs (TPAH25) concentrations ranged from 11.6 to 223 ng g−1. Molecular profiles of aliphatic hydrocarbons and PAHs reflect the contribution of both natural (epicuticular plant waxes) and anthropogenic (degraded petroleum products, unburned fossil fuels and combustion of petroleum, grass, wood and coal) compounds in deep EMS sediments, with hydrocarbon mixtures displaying significant regional variability. Hydrocarbon concentrations correlated significantly with the Total Organic Carbon (TOC) content of sediments, indicating that organic carbon exerts an important control on their transport and fate in the study area, while strong sub-basin and mesoscale variability of water masses also impact their regional characteristics. Major findings of this study support that deep basins/canyons of the EMS could act as traps of both natural and anthropogenic hydrocarbons.

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Shi, Zhen Jing, Meng Xiang Fang, Qing Hui Wang, and Zhong Yang Luo. "Studies on Rapid Pyrolysis Characteristics of Huainan Coal." Applied Mechanics and Materials 316-317 (April 2013): 32–35. http://dx.doi.org/10.4028/www.scientific.net/amm.316-317.32.

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This paper aims to investigate the rapid pyrolysis characteristics of Huainan coal using a tube furnace. Influence of temperature on yields and compounds of tar and char are tested. The result shows that aliphatic chains break gradually with increasing pyrolysis temperature. This leads an increase in aromaticity. Maximum tar yields were obtained at about 550°C, the char yields decreased and the gas yields increased with the pyrolysis temperature. The tar was isolated to aliphatic hydrocarbon aromatic hydrocarbon, non hydrocarbon and asphaltene, and characterized by chromatography-mass spectrometry (GC/MS). The main content of tar include normal alkanes from C16-C30, two-,three- and four-ring aromatic hydrocarbons and alkyl-substituted hydroaromatic derivatives of polycyclic, phenols, indoles, quinines esters and others compounds.

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12

Farjadfard, Sima, Seyyed Mehdi Borghei, Amir Hessam Hassani, Bagher Yakhchali, Mehdi Ardjmand, and Majid Zeinali. "Efficient biodegradation of naphthalene by a newly characterized indigenous Achromobacter sp. FBHYA2 isolated from Tehran Oil Refinery Complex." Water Science and Technology 66, no. 3 (August 1, 2012): 594–602. http://dx.doi.org/10.2166/wst.2012.217.

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A bacterial strain, FBHYA2, capable of degrading naphthalene, was isolated from the American Petroleum Institute (API) separator of the Tehran Oil Refinery Complex (TORC). Strain FBHYA2 was identified as Achromobacter sp. based on physiological and biochemical characteristics and also phylogenetic similarity of 16S rRNA gene sequence. The optimal growth conditions for strain FBHYA2 were pH 6.0, 30 °C and 1.0% NaCl. Strain FBHYA2 can utilize naphthalene as the sole source of carbon and energy and was able to degrade naphthalene aerobically very fast, 48 h for 96% removal at 500 mg/L concentration. The physiological response of Achromobacter sp., FBHYA2 to several hydrophobic chemicals (aliphatic and aromatic hydrocarbons) was also investigated. No biosurfactant was detected during bacterial growth on any aliphatic/aromatic hydrocarbons. The results of hydrophobicity measurements showed no significant difference between naphthalene- and LB-grown cells. The capability of the strain FBHYA2 to degrade naphthalene completely and rapidly without the need to secrete biosurfactant may make it an ideal candidate to remediate polycyclic aromatic hydrocarbon (PAH)-contaminated sites.

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Saldarriaga, Hugo, Rafael Villalobos, Gisela Solano, Omar Amador, Roberto Gaspariano, Ricardo Palma, and Zenaida Munive. "ALIPHATIC, POLYCYCLIC AROMATIC HYDROCARBONS AND NITRATED-POLYCYCLIC AROMATIC HYDROCARBONS IN PM10IN SOUTHWESTERN MEXICO CITY." Polycyclic Aromatic Compounds 28, no. 4-5 (November 11, 2008): 578–97. http://dx.doi.org/10.1080/10406630802373822.

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14

Foght, J. M., and D. W. S. Westlake. "Degradation of polycyclic aromatic hydrocarbons and aromatic heterocycles by a Pseudomonas species." Canadian Journal of Microbiology 34, no. 10 (October 1, 1988): 1135–41. http://dx.doi.org/10.1139/m88-200.

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Enrichment cultures were established with the aromatic fraction of a crude oil and screened for aromatic-degrading pseudomonads, using a sprayed plate technique. One isolate identified as Pseudomonas sp. HL7b was chosen for further study because it oxidized several polycyclic aromatic hydrocarbons and aromatic heterocycles without an apparent lag. Using capillary gas chromatography, spectrophotometry, and radiorespirometry, it was found to be capable of mineralizing and (or) oxidizing a wide range of polycyclic aromatic hydrocarbons, S-, N-, and O-heterocyclic analogues, and alkyl polycyclic aromatic hydrocarbons, but not aliphatic hydrocarbons. The isolate displayed two colonial morphologies which correlated with variation in degradative phenotype and hydrophobicity as measured by polystyrene adherence. Four cryptic plasmids were observed in both colonial types. Pseudomonas sp. HL7b degraded dibenzothiophene co-metabolically by a recognized pathway, but this degradation was constitutive, rather than inducible as reported for other bacteria.

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Purohit, V., and R. A. Orzel. "Polypropylene: A Literature Review of the Thermal Decomposition Products and Toxicity." Journal of the American College of Toxicology 7, no. 2 (March 1988): 221–42. http://dx.doi.org/10.3109/10915818809014521.

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This report presents a comprehensive literature review of the thermal decomposition products of polypropylene evolved under pyrolytic and oxidative conditions and the acute toxicity of combustion products of this polymer. Generally, the pyrolysis products of polypropylene (300–700°C) were aliphatic saturated and unsaturated hydrocarbons. The combustion of polypropylene in air (200–600°C) produced oxygenated hydrocarbons, aromatic hydrocarbons, aliphatic hydrocarbons, CO, CO2, and H2O. In general, as combustion temperature and time increased, the proportions of oxygenated and aliphatic hydrocarbons decreased, whereas the proportion of aromatic hydrocarbons increased. Using the University of San Francisco/National Aeronautical and Space Administration (USF/NASA) method under the fixed temperature program, time to death in mice caused by the combustion products of polypropylene decreased as the temperature was increased. Under the rising temperature mode, time to death decreased when polypropylene was combusted under airflow as compared to no airflow conditions. CO levels generated by the combustion of polypropylene were sufficient to produce the lethal effects observed. Using a test method developed at the University of Michigan, the combustion products of polypropylene were found to be 26 times more toxic under dynamic conditions (rising temperature) than under static conditions (fixed temperature).

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Payne, J. F., L. L. Fancey, J. Hellou, M. J. King, and G. L. Fletcher. "Aliphatic hydrocarbons in sediments: a chronic toxicity study with winter flounder (Pleuronectes americanus) exposed to oil well drill cuttings." Canadian Journal of Fisheries and Aquatic Sciences 52, no. 12 (December 1, 1995): 2724–35. http://dx.doi.org/10.1139/f95-861.

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Most studies on the chronic toxicity of hydrocarbons have focused on the polycyclic aromatic component; however, information is also required on the chronic toxicity of other classes of hydrocarbons. This need has been brought to the forefront by the controversy about the use of aliphatic hydrocarbon-based drilling fluids at petroleum development sites in the marine environment. Dose–response relationships were studied for a variety of indices in a chronic toxicity study with winter flounder (Pleuronectes americanus) exposed to sediments contaminated with drill cuttings enriched in hydrocarbons. The indices investigated were biologically meaningful and included organ and body condition indices, muscle and liver energy reserves, mixed-function oxygenase detoxification enzymes, blood parameters, and liver and gill histopathology. There was no evidence of dose–response relationships and most indices remained unaffected even at the highest exposure level. The study supports the hypothesis that the aliphatic component of complex hydrocarbon mixtures is relatively nontoxic, and it will be of particular interest for evaluating the scope of environmental risks associated with the use of oil-base drilling fluids in the marine environment.

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Kemp, Jesse M., Lerin R. Luckett-Chastain, Kaitlin N. Calhoun, Benjamin Frempah, Tayler R. Schartz, Linda E. Harty, Philip M. Kemp, and Randle M. Gallucci. "Evaluation of skin irritation following weathered crude oil exposure in two mouse strains." Toxicology and Industrial Health 36, no. 10 (August 18, 2020): 788–99. http://dx.doi.org/10.1177/0748233720944354.

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Petroleum crude oil spills are common and vary in size and scope. Spill response workers throughout the course of remediation are exposed to so-called weathered oil and are known to report diverse health effects, including contact dermatitis. A murine model of repeated exposure to weathered marine crude oil was employed utilizing two strains of mice, C57BL/6 and BALB/c, to investigate the pathology of this irritant and identify the principal hydrocarbon components deposited in skin. Histopathology demonstrated clear signs of irritation in oil-exposed skin from both mouse strains, characterized by prominent epidermal hyperplasia (acanthosis). BALB/c mice exposed to oil demonstrated more pronounced irritation compared with C57BL/6 mice, which was characterized by increased acanthosis as well as increased inflammatory cytokine/chemokine protein expression of IL-1β, IL-6, CXCL10, CCL2, CCL3, CCL4, and CCL11. A gas chromatography/mass spectrometry method was developed for the identification and quantification of 42 aliphatic and EPA priority aromatic hydrocarbons from full thickness skin samples of C57BL/6 and BALB/c mice exposed to oil samples. Aromatic hydrocarbons were not detected in skin; however, aliphatic hydrocarbons in skin tended to accumulate with carbon numbers greater than C16. These preliminary data and observations suggest that weathered crude oil is a skin irritant and this may be related to specific hydrocarbon components, although immune phenotype appears to impact skin response as well.

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Costas, Miguel, and Bengt Kronberg. "Thermodynamics of aliphatic and aromatic hydrocarbons in water." Biophysical Chemistry 74, no. 1 (August 1998): 83–87. http://dx.doi.org/10.1016/s0301-4622(98)00167-7.

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Sicre, M. A., J. C. Marty, A. Saliot, X. Aparicio, J. Grimalt, and J. Albaiges. "Aliphatic and Aromatic Hydrocarbons in the Mediterranean Aerosol." International Journal of Environmental Analytical Chemistry 29, no. 1-2 (March 1987): 73–94. http://dx.doi.org/10.1080/03067318708078412.

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Cui, Weihong, and Bradford B. Wayland. "Hydrocarbon C-H bond activation by rhodium porphyrins." Journal of Porphyrins and Phthalocyanines 08, no. 02 (February 2004): 103–10. http://dx.doi.org/10.1142/s108842460400009x.

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Rhodium porphyrins provide a variety of C-H bond reactions with both aromatic and aliphatic hydrocarbons that acquire unusual selectivity in part through the steric requirements of the porphyrin ligand. Rhodium(III) porphyrins selectively react with aromatic C-H bonds by electrophilic substitution with the virtual exclusion of aliphatic C-H bond activation. Rhodium(II) porphyrins react by a metal-centered radical pathway with alkyl aromatics and alkanes selectively at the alkyl C-H bond with total exclusion of aromatic C-H bond activation. Reactions of rhodium(II) metalloradicals with alkyl C-H bonds have large deuterium isotope effects, small activation enthalpies and large negative activation entropies consistent with a near linear symmetrical four-centered transition state ( Rh ˙⋯ H ⋯ C ⋯˙Rh). The nature of this transition state and the dimensions of rhodium porphyrins provide steric constraints that preclude aromatic C-H bond reactions and give high kinetic preference for methane activation as the smallest alkane substrate. Rhodium(II) tethered diporphyrin bimetalloradical complexes convert the C-H bond reactions to bimolecular processes with dramatically increased reaction rates and high selectivity for methane activation.

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Guilhaumou, Nicole, Nathalie Szydlowskii, and Bernard Pradier. "Characterization of hydrocarbon fluid inclusions by infra-red and fluorescence microspectrometry." Mineralogical Magazine 54, no. 375 (June 1990): 311–24. http://dx.doi.org/10.1180/minmag.1990.054.375.17.

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AbstractLiquid-hydrocarbon-bearing fluid inclusions have often been described associated with petroleum occurrences and diagenetic sediments. Infra-red microspectrometry allows characterization of fluid inclusions greater than 20 µm by establishing the presence of aliphatic and aromatic hydrocarbons as well as associated H2O, CO2 and CH4. Semi-quantitative analyses have been made by focussing on gaseous and liquid phases separately. Some CH2/CH3 and CO2/CH4 ratios have been determined by this method.Fluorescence microspectrometry permits precise measurements of the fluorescence emission spectrum of chromophore-bearing organic phases (essentially aromatic hydrocarbons) in fluid inclusions greater than 10 µm. Such a spectrum is a function of both the gross composition of the trapped oil and its thermal history.Both of these methods lead to the in situ characterization of hydrocarbon fluid inclusions. They are useful in providing a quantifiable distinction between different oil generations trapped during mineral growth in diagenetic and epigenetic minerals.

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Zeliger, Harold I., and Boguslaw Lipinski. "Physiochemical basis of human degenerative disease." Interdisciplinary Toxicology 8, no. 1 (March 1, 2015): 15–21. http://dx.doi.org/10.1515/intox-2015-0003.

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AbstractThe onset of human degenerative diseases in humans, including type 2 diabetes, cardiovascular disease, neurological disorders, neurodevelopmental disease and neurodegenerative disease has been shown to be related to exposures to persistent organic pollutants, including polychlorinated biphenyls, chlorinated pesticides, polybrominated diphenyl ethers and others, as well as to polynuclear aromatic hydrocarbons, phthalates, bisphenol-A and other aromatic lipophilic species. The onset of these diseases has also been related to exposures to transition metal ions. A physiochemical mechanism for the onset of degenerative environmental disease dependent upon exposure to a combination of lipophilic aromatic hydrocarbons and transition metal ions is proposed here. The findings reported here also, for the first time, explain why aromatic hydrocarbons exhibit greater toxicity than aliphatic hydrocarbons of equal carbon numbers.

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Keeley, D. F., and J. R. Meriwether. "Hydrocarbons From U.S. Gulf Coast Geopressured Brines." Journal of Energy Resources Technology 110, no. 3 (September 1, 1988): 177–82. http://dx.doi.org/10.1115/1.3231379.

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U.S. Gulf Coast geopressured brines studied to date contain small amounts of C6+ hydrocarbons which are primarily aromatic in nature. They range from benzene to substituted anthracenes. In addition, the brines contain a variety of ions and light, C1 to C6, aliphatic hydrocarbons. The primarily aromatic hydrocarbon mixture was collected at −78.5°C and is referred to as a “cryocondensate.” It contains at least 95 different compounds and, from the carbon isotropic ratios, appears to be of terrestrial plant origin. For the only U.S. DOE geopressured energy design well studied for an extended period of time, i.e., the Glady’s McCall well, the concentration of the cryocondensate in the brine was observed to increase prior to the onset of oil production. It is postulated that the change in the brine cryocondensate concentration as a function of the cumulative brine volume produced from the wells results from an extraction of additional aromatic components from oil migrating into the production zone from adjacent shale. When sufficient oil has migrated, it is produced along with the brine.

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Garrido-Sanz, Daniel, Miguel Redondo-Nieto, María Guirado, Oscar Pindado Jiménez, Rocío Millán, Marta Martin, and Rafael Rivilla. "Metagenomic Insights into the Bacterial Functions of a Diesel-Degrading Consortium for the Rhizoremediation of Diesel-Polluted Soil." Genes 10, no. 6 (June 14, 2019): 456. http://dx.doi.org/10.3390/genes10060456.

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Diesel is a complex pollutant composed of a mixture of aliphatic and aromatic hydrocarbons. Because of this complexity, diesel bioremediation requires multiple microorganisms, which harbor the catabolic pathways to degrade the mixture. By enrichment cultivation of rhizospheric soil from a diesel-polluted site, we have isolated a bacterial consortium that can grow aerobically with diesel and different alkanes and polycyclic aromatic hydrocarbons (PAHs) as the sole carbon and energy source. Microbiome diversity analyses based on 16S rRNA gene showed that the diesel-degrading consortium consists of 76 amplicon sequence variants (ASVs) and it is dominated by Pseudomonas, Aquabacterium, Chryseobacterium, and Sphingomonadaceae. Changes in microbiome composition were observed when growing on specific hydrocarbons, reflecting that different populations degrade different hydrocarbons. Shotgun metagenome sequence analysis of the consortium growing on diesel has identified redundant genes encoding enzymes implicated in the initial oxidation of alkanes (AlkB, LadA, CYP450) and a variety of hydroxylating and ring-cleavage dioxygenases involved in aromatic and polyaromatic hydrocarbon degradation. The phylogenetic assignment of these enzymes to specific genera allowed us to model the role of specific populations in the diesel-degrading consortium. Rhizoremediation of diesel-polluted soil microcosms using the consortium, resulted in an important enhancement in the reduction of total petroleum hydrocarbons (TPHs), making it suited for rhizoremediation applications.

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Page, David S., Edward S. Gilfillan, Judith C. Foster, Erin Pendergast, Linda Gonzalez, and Donna Vallas. "COMPOSITIONAL CHANGES IN DISPERSED CRUDE OIL IN THE WATER COLUMN DURING A NEARSHORE TEST SPILL." International Oil Spill Conference Proceedings 1985, no. 1 (February 1, 1985): 521–30. http://dx.doi.org/10.7901/2169-3358-1985-1-521.

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ABSTRACT As part of the American Petroleum Institute sponsored tidal area dispersant project involving two test spills of Murban crude oil in Long Cove, Searsport, Maine in August, 1981, water samples were collected. This paper deals with the analytical results for the analyses of water samples collected for analysis of non-volatile hydrocarbons by: infrared spectrophotometric quantitation of total CCl4 extractables, and gravimetric analysis of aliphatic and aromatic hydrocarbon fractions followed by capillary gas chromatography. In the dispersant-treated oil discharge area, there were two primary water sampling locations during the discharge phase of the experiment: an upper intertidal area (maximum depth = 2 meters) and a lower intertidal area (maximum depth = 3.5 meters). The gas chromatographic data for the water samples were treated numerically to obtain parameters whose values reflect the extent of dispersed oil weathering. For the aliphatics, the peak area ratio for n C14/n C18 was calculated for each sample. For the aromatics, the ratio for the peak area sum of the mono, di, and trimethyl naphthalenes to that for the mono, di, tri, and tetramethyl dibenzothiophenes was determined for each sample. At both sampling locations, dispersed oil in water sampled 10 cm off the bottom consistently had a smaller fraction of lower boiling aliphatic and aromatic hydrocarbons than water sampled at the same place and the same time ½ meter below the surface. In addition, the data show that there is a 12–50 fold decrease in hydrocarbon concentration on going from near surface to near bottom at any given time, even in water as shallow as 2 meters. The data indicate that the primary mechanism for hydrocarbon loss involves volatilization of hydrocarbon fractions. Analyses of water samples taken from submerged plumes of dispersed oil outside the sampling areas demonstrated slower loss of low boiling components consistent with the importance of atmospheric exchange in the weathering process. In the chemical dispersal of an oil spill, it may be most advantageous to use mixing methods that minimize vertical mixing in order to maintain a high concentration of emulsified oil in the upper ½ meter water layer. This will maximize the extent of loss of lower boiling hydrocarbon components into the atmosphere and thus minimize the toxicity of any dispersed oil fractions that diffuse downward and interact with benthic communities.

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Sotsky, J. B., C. W. Greer, and R. M. Atlas. "Frequency of genes in aromatic and aliphatic hydrocarbon biodegradation pathways within bacterial populations from Alaskan sediments." Canadian Journal of Microbiology 40, no. 11 (November 1, 1994): 981–85. http://dx.doi.org/10.1139/m94-157.

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A significant proportion of the naturally occurring hydrocarbon-degrading populations within Alaskan sediments affected by the Exxon Valdez oil spill had both the xylE and alkB genes and could convert hexadecane and naphthalene to carbon dioxide; a greater proportion of the population had xylE than had alkB, reflecting the composition of the residual oil at the time of sampling; nearly equal populations with xylE alone, alkB alone, and xylE + alkB genes together were found after exposure to fresh crude oil; populations with xylE lacking alkB increased after enrichment on naphthalene. Thus, the genotypes of hydrocarbon-degrading populations reflected the composition of the hydrocarbons to which they were exposed.Key words: hydrocarbon biodegradation, aromatic hydrocarbon biodegradation, aliphatic hydrocarbon biodegradation, alkB, xylE.

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Syed, Khajamohiddin, Aleksey Porollo, Ying Wai Lam, Paul E. Grimmett, and Jagjit S. Yadav. "CYP63A2, a Catalytically Versatile Fungal P450 Monooxygenase Capable of Oxidizing Higher-Molecular-Weight Polycyclic Aromatic Hydrocarbons, Alkylphenols, and Alkanes." Applied and Environmental Microbiology 79, no. 8 (February 15, 2013): 2692–702. http://dx.doi.org/10.1128/aem.03767-12.

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ABSTRACTCytochrome P450 monooxygenases (P450s) are known to oxidize hydrocarbons, albeit with limited substrate specificity across classes of these compounds. Here we report a P450 monooxygenase (CYP63A2) from the model ligninolytic white rot fungusPhanerochaete chrysosporiumthat was found to possess a broad oxidizing capability toward structurally diverse hydrocarbons belonging to mutagenic/carcinogenic fused-ring higher-molecular-weight polycyclic aromatic hydrocarbons (HMW-PAHs), endocrine-disrupting long-chain alkylphenols (APs), and crude oil aliphatic hydrocarbonn-alkanes. A homology-based three-dimensional (3D) model revealed the presence of an extraordinarily large active-site cavity in CYP63A2 compared to the mammalian PAH-oxidizing (CYP3A4, CYP1A2, and CYP1B1) and bacterial aliphatic-hydrocarbon-oxidizing (CYP101D and CYP102A1) P450s. This structural feature in conjunction with ligand docking simulations suggested potential versatility of the enzyme. Experimental characterization using recombinantly expressed CYP63A2 revealed its ability to oxidize HMW-PAHs of various ring sizes, including 4 rings (pyrene and fluoranthene), 5 rings [benzo(a)pyrene], and 6 rings [benzo(ghi)perylene], with the highest enzymatic activity being toward the 5-ring PAH followed by the 4-ring and 6-ring PAHs, in that order. Recombinant CYP63A2 activity yielded monohydroxylated PAH metabolites. The enzyme was found to also act as an alkane ω-hydroxylase that oxidizedn-alkanes with various chain lengths (C9to C12and C15to C19), as well as alkyl side chains (C3to C9) in alkylphenols (APs). CYP63A2 showed preferential oxidation of long-chain APs and alkanes. To our knowledge, this is the first P450 identified from any of the biological kingdoms that possesses such broad substrate specificity toward structurally diverse xenobiotics (PAHs, APs, and alkanes), making it a potent enzyme biocatalyst candidate to handle mixed pollution (e.g., crude oil spills).

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B., Manoj, Kunjomana A. G., and Chandrasekharan K. A. "Extraction of carbonyl, carboxyl functional groups and silicate minerals from coal and its characterization using infrared spectroscopy." Mapana - Journal of Sciences 8, no. 1 (May 31, 2009): 1–9. http://dx.doi.org/10.12723/mjs.14.1.

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This paper reports the characterization ond demineralization of coal with HCL, Chloroform and water. The residual cool from each treatment was analyzed using FTIR spectroscopy to understand the effect of chemical leaching and water washing on the sample structure for aliphatic and aromatic CH bonds. Investigation of the mineral content in the sample and its change with above said treatment was also done. Absoptivities for aromatic CH bond stretching and out-of-plane bending modes were found to be independent of the structure. For structural analysis of cool, the structural independence of absoptivities for aromatic CH bonds allows o reliable assessment of aromatic hydrogen content in cools. Evaluation of aliphatic hydrogen content was greatly affected with the presence of chloroform extractable in the cool, which contain highly aliphatic material with a high absoptivities of aliphatic CH bonds, especially those in long methylene chains. The obsoptivities of heteroatom-rich fractions were lower than those of hydrocarbons and did not show any dependence on hydrogen aromaticity of the sample.

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Shimoyama, Daisuke, Ryo Sekiya, and Takeharu Haino. "Absorption of chemicals in amorphous trisresorcinarene." Chemical Communications 56, no. 83 (2020): 12582–85. http://dx.doi.org/10.1039/d0cc05066k.

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Trisresorcinarene is an interesting class of macrocyclic host. Its unique structure and insolubility allow to function as a amorphous solid absorbent capable of absorbing various aromatic and aliphatic hydrocarbons.

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Tolosa, Imma, Stephen de Mora, Mohammad Reza Sheikholeslami, Jean-Pierre Villeneuve, Jean Bartocci, and Chantal Cattini. "Aliphatic and aromatic hydrocarbons in coastal caspian Sea sediments." Marine Pollution Bulletin 48, no. 1-2 (January 2004): 44–60. http://dx.doi.org/10.1016/s0025-326x(03)00255-8.

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Baek, Kyung-Hwa, Byung-Dae Yoon, Hee-Mock Oh, Hee-Sik Kim, and In-Sook Lee. "Biodegradation of Aliphatic and Aromatic Hydrocarbons byNocardiasp. H17-1." Geomicrobiology Journal 23, no. 5 (August 2006): 253–59. http://dx.doi.org/10.1080/01490450600760633.

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Meindersma, G. Wytze, Anita (J G. ). Podt, Marianne B. Klaren, and André B. de Haan. "SEPARATION OF AROMATIC AND ALIPHATIC HYDROCARBONS WITH IONIC LIQUIDS." Chemical Engineering Communications 193, no. 11 (November 2006): 1384–96. http://dx.doi.org/10.1080/00986440500511403.

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Wakeham, Stuart G. "Aliphatic and polycyclic aromatic hydrocarbons in Black Sea sediments." Marine Chemistry 53, no. 3-4 (August 1996): 187–205. http://dx.doi.org/10.1016/0304-4203(96)00003-5.

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Rocher, V., S. Azimi, R. Moilleron, and G. Chebbo. "Biofilm in combined sewers: wet weather pollution source and/or dry weather pollution indicator?" Water Science and Technology 47, no. 4 (February 1, 2003): 35–43. http://dx.doi.org/10.2166/wst.2003.0215.

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In a sewer trunk, three kinds of deposit, acting as potential wet weather sources, can be found: the biofilm, the organic layer and the gross bed sediment. This research program, on the “Le Marais” catchment (Paris, France), focused on the biofilm. The objectives were to describe, using a Transmission Electronic Microscope, the architecture of the sewer biofilm and to investigate the contents and the distributions of aliphatic and aromatic hydrocarbons in biofilm. The electron micrographs illustrated a uniform film of bacteria totally covering the surface of a thick organic matrix. A large cohesion of the cell layer and organic matrix complex, due to exopolysaccharides, was noticed. Hence, the hydrocarbon contents were measured not only in the biofilm itself, but in this complex. Our results showed that almost all hydrocarbons were stored in the gross bed sediment and the organic layer and, consequently, the biofilm was not an important potential source of wet weather pollution. Comparison between the hydrocarbon distributions in the biofilm and in the other deposits indicated that the biofilm could be used as an indicator of the aliphatic hydrocarbon pollution in the organic layer.

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Ruzani, Raihanah Na Ilah, Suhaimi Suratman, Muhammad Fais Fadzil, Pang Swee Yun, Nur Shahirah Rozmi, and Norhayati Mohd Tahir. "Determination of Aliphatic and Polycyclic Aromatic Hydrocarbons in Marine Core Sediments off Johor, Malaysia." Oriental Journal Of Chemistry 37, no. 4 (August 30, 2021): 928–37. http://dx.doi.org/10.13005/ojc/370422.

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Aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs) were studied in two sediment cores of southern South China Sea off Johor coastal area. The concentrations of the total identified resolved aliphatic hydrocarbons (TiRAHs) in the coastal station (STC104) ranged from 0.35 to 2.07 µg/g while the offshore station (STC100) varied from 0.05 to 14.7 µg/g. The concentrations of total PAHs were varied from not detected to 33.9 ng/g. The nalkanes distribution in STC104 were predominant in short chain carbons from marine productivity, petroleum mixture and minor higher plant input, while STC100 exhibited a bimodal distribution with mixed input of marine and terrestrial origin. PAHs isomer ratios cross-plot have showed mixed input of pyrogenic and petrogenic inputs while perylene was dominated in STC100 followed by fossil fuels and pyrogenic source. Presence of perylene in both cores suggesting the contribution of biogenic sources. Principal component analysis was used to cluster the relationship of the hydrocarbons at both sediment cores.

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Venturini, Natalia, Luiz Roberto Tommasi, Márcia C. Bícego, and César C. Martins. "Characterization of the benthic environment of a coastal area adjacent to an oil refinery, Todos os Santos Bay (NE-Brazil)." Brazilian Journal of Oceanography 52, no. 2 (June 2004): 123–34. http://dx.doi.org/10.1590/s1679-87592004000200004.

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In order to determine the sedimentological and physico-chemical characteristics of the benthic environment and also the level, distribution and probable sources of aliphatic and polycyclic aromatic hydrocarbons, sediment samples were collected at 28 stations in the northeast portion of Todos os Santos Bay. The centre and the east region of the study area showed characteristics of depositional environments with the predominance of silt and clay and high percentages of TOC, nitrogen and sulphur. The molar C/N ratios varied between 8.8 and 27.6 indicating a mixed origin of organic matter with variable marine and continental contributions. Total aliphatic hydrocarbon concentrations ranged between 1.56 and 246.91 µg.g-1 dry weight, corresponding the high concentrations to the stations situated in the centre and in the east region of the study area. The UCM represented between 60 and 96% of the total aliphatic hydrocarbons, indicating a high degree of anthropogenic contribution and the presence of petroleum degraded residues. Total PAH concentrations varied from 8 to 4163 ng.g-1 dry weight. The highest total PAH concentration was recorded at station 5 situated adjacent to the oil refinery.

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Rosik-Dulewska, Czesława, Teresa Krzyśko-Łupicka, Tomasz Ciesielczuk, and Łukasz Kręcidło. "Hydrogen peroxide as a biodegradation stimulator in remediation processes of soils heavily contaminated with petrochemicals." Polish Journal of Chemical Technology 17, no. 2 (June 1, 2015): 17–22. http://dx.doi.org/10.1515/pjct-2015-0023.

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Abstract The soil contaminated with petroleum products must be excluded from the crops and treated to reclamation processes. Natural processes of decomposition of hydrocarbon compounds go very slow, so it is necessary to use bioaugumentation or stimulation in order to accelerate the return of the soil to high culture. In this study the effect of hydrogen peroxide on the process of cleaning soil strongly contaminated with pertochemicals was investigated. For this purpose, a pot experiment lasting 60 days was carried. The dynamics of changes in the population of filamentous fungi, yeasts and bacteria were examined and also content of aliphatic hydrocarbons (n-alkanes), monoaromatic and polycyclic aromatic hydrocarbons (PAHs). Experimental use of hydrogen peroxide in the process of biodegradation of petroleum compounds assisted in the analyzed soil led to an increase of the number of grampositive bacteria during the test. Stimulation of oil products biodegradation by hydrogen peroxide also increased by 35% decomposition efficiency of aliphatic hydrocarbons (C8-C40) and about 50% PAH’s in comparison to control samples without hydrogen peroxide. There was no influence of hydrogen peroxide on the content of monoaromatic hydrocarbons (BTEX) with respect to controls, although in the end of experiment, the total concentration decreased by about 50% compared to the initial content.

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Yao, Hua, Bo Xie, Xiaoyang Zhong, Shengzhou Jin, Sen Lin, and Zhaohua Yan. "Copper-catalyzed direct amination of benzylic hydrocarbons and inactive aliphatic alkanes with arylamines." Organic & Biomolecular Chemistry 18, no. 17 (2020): 3263–68. http://dx.doi.org/10.1039/d0ob00491j.

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A new synthetic method toward direct C–N bond formation through saturated C–H amination of benzylic hydrocarbons and inactive aliphatic alkanes with primary aromatic amines under an inexpensive catalyst/oxidant (Cu/DTBP) system has been developed.

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Park, Young-Kwon, Myung Lang Yoo, and Sung Hoon Park. "Effects of Acid Characteristics of Nanoporous MCM-48 on the Pyrolysis Product Distribution of Waste Pepper Stem." Journal of Nanomaterials 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/596584.

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Nanoporous catalysts Si-MCM-48 and Al-MCM-48 were applied for the first time to the catalytic pyrolysis of waste pepper stem. Pyrolysis experiments were conducted at 550°C using Py-GC/MS to examine the product distribution rapidly. Phenolics were shown to be the most abundant product species of noncatalytic pyrolysis, whereas aliphatic and aromatic hydrocarbons were produced marginally. On the other hand, much larger quantities of furans and aliphatic and aromatic hydrocarbons were produced from the catalytic pyrolysis over MCM-48, while the production of phenolics was suppressed significantly. Al-MCM-48 showed a much higher catalytic activity than Si-MCM-48, which was attributed to its much higher acidity. The results of this study indicate that valuable chemicals can be produced from waste pepper stem using catalytic pyrolysis over an acidic nanoporous catalyst.

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Ge, Wu Jie, Qun Shao, Hui Xu, and Ya Li Wan. "Low Temperature Oxidation Effects on Lignite Molecular Structure." Advanced Materials Research 550-553 (July 2012): 2797–800. http://dx.doi.org/10.4028/www.scientific.net/amr.550-553.2797.

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The paper studied the change of the coal characteristics based on the influence of lignite naturally oxidated in air. The original lignite and lignite naturally oxidated under different time were analyzed by the FTIR technology. The reason that metamorphism of lignite was vulnerable by oxygen was analyzed from the side of coal molecular structure. It indicates that lignite of a low rank coal easily oxidated is mainly because lignite has more active groups in coal molecular such as methyl, methylene, hydroxyl, aromatic ether, oxygen button and ether key. In lignite molecular, side chains of aromatic ring structure unit is firstly oxidized. The bridge button or side chains of coal molecular structure unit are easily oxidized at the same time with the structure of the bridge between units fracturing oxidation. Number of aromatic hydrocarbons remains stable after oxidation. General trend of cycloparafin hydrocarbon as well as aliphatic hydrocarbon are gradually reduced over the oxidized time.

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Liu, Xiaoyang, Haodan Pan, Chuang Guo, Xiaojing Di, and Hongxiang Hu. "Effect of Double Transition Metal Salt Catalyst on Fushun Oil Shale Pyrolysis." Scanning 2020 (November 4, 2020): 1–14. http://dx.doi.org/10.1155/2020/6685299.

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Shale ash (SA) as the carrier, the ratio of Cu to Ni in the Cu-Ni transition metal salt being, respectively, 1 : 0, 2 : 1, 1 : 1, 1 : 2, 0 : 1, the double transition metal salt catalyst (CumNin/SA) was prepared to explore the effect of such catalysts on the pyrolysis behavior and characteristics of Fushun OS. The research results show that the temperature ( T max ) corresponding to the maximum weight loss rate decreased by 12.9°C, 4.0°C, and 3.6°C; and the apparent activation energy decreased by 35.2%, 33.9%, and 29.6%, respectively, after adding catalysts Cu0Ni1/SA in pyrolysis. The addition of Cu0Ni1/SA and Cu2Ni1/SA further improves the shale oil (SO) yield of 3.5% and 3.1%, respectively. Cu0Ni1/SA produces more aromatic hydrocarbons, which, however, weakens the stability of SO and is of toxicity in use. After analyzing the pyrolysis product—semicoke (SC) and SO—with ATR-FTIR and GC-MS methods, CumNin/SA promotes the secondary cracking and aromatization of OS pyrolysis, increasing the content of the compound of olefins and aromatics in SO, and hastening the decomposition of long-chain aliphatic hydrocarbons to short-chain aliphatic hydrocarbons.

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Goodpaster, John V., and Victoria L. McGuffin. "Selective Fluorescence Quenching of Polycyclic Aromatic Hydrocarbons by Aliphatic Amines." Analytical Chemistry 72, no. 5 (March 2000): 1072–77. http://dx.doi.org/10.1021/ac991106j.

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Borsdorf, Helko, Hubert Schelhorn, Johannes Flachowsky, Hans-Rüdiger Döring, and Joachim Stach. "Corona discharge ion mobility spectrometry of aliphatic and aromatic hydrocarbons." Analytica Chimica Acta 403, no. 1-2 (January 2000): 235–42. http://dx.doi.org/10.1016/s0003-2670(99)00567-x.

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Braddock, Joan F., James L. Walworth, and Kathleen A. McCarthy. "Biodegradation of Aliphatic vs. Aromatic Hydrocarbons in Fertilized Arctic Soils." Bioremediation Journal 3, no. 2 (April 1999): 105–16. http://dx.doi.org/10.1080/10889869991219253.

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Stout, Scott A. "Aliphatic and aromatic triterpenoid hydrocarbons in a Tertiary angiospermous lignite." Organic Geochemistry 18, no. 1 (January 1992): 51–66. http://dx.doi.org/10.1016/0146-6380(92)90143-l.

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Das, A. K., and B. L. Jha. "Molecular interactions in binary mixtures of DMSO-aromatic/aliphatic hydrocarbons." Journal of Molecular Liquids 50 (October 1991): 155–86. http://dx.doi.org/10.1016/0167-7322(91)80043-4.

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Grzybowski, Janusz, Jan Halkiewicz, Henryk Lamparczyk, and Aleksander Radecki. "Aliphatic and polycyclic aromatic hydrocarbons in the southern Baltic sea." Marine Pollution Bulletin 18, no. 5 (May 1987): 247–48. http://dx.doi.org/10.1016/0025-326x(87)90467-x.

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Ben-Horin, Narda, Uzi Even, and Joshua Jortner. "Microscopic and macroscopic solvation of aromatic molecules in aliphatic hydrocarbons." Chemical Physics Letters 177, no. 2 (February 1991): 153–60. http://dx.doi.org/10.1016/0009-2614(91)90061-d.

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Pereira, J., F. A. Agblevor, and S. H. Beis. "The Influence of Process Conditions on the Chemical Composition of Pine Wood Catalytic Pyrolysis Oils." ISRN Renewable Energy 2012 (December 19, 2012): 1–9. http://dx.doi.org/10.5402/2012/167629.

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Pine wood samples were used as model feedstock to study the properties of catalytic fast pyrolysis oils. The influence of two commercial zeolite catalysts (BASF and SudChem) and pretreatment of the pine wood with sodium hydroxide on pyrolysis products were investigated. The pyrolysis oils were first fractionated using column chromatography and characterized using GC-MS. Long chain aliphatic hydrocarbons, levoglucosan, aldehydes and ketones, guaiacols/syringols, and benzenediols were the major compounds identified in the pyrolysis oils. The catalytic pyrolysis increased the polycyclic hydrocarbons fraction. Significant decreases in phthalate derivatives using SudChem and long chain aliphatics using BASF catalyst were observed. Significant amounts of aromatic heterocyclic hydrocarbons and benzene derivatives were formed, respectively, using BASF and SudChem catalysts. Guaiacyl/syringyl and benzenediols derivatives were partly suppressed by the zeolite catalysts, while the sodium hydroxide treatment enriched phenolic derivatives. Zeolite catalyst and sodium hydroxide were employed together; they showed different results for each catalyst.

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Panwar, D. S., Ram Chandra Chaurasia, V. K. Saxena, A. K. Singh, and Akanksha. "Geochemical investigation of hydrocarbon generation potential of coal from Raniganj Basin, India." Journal of Petroleum Exploration and Production Technology 11, no. 10 (September 4, 2021): 3627–36. http://dx.doi.org/10.1007/s13202-021-01281-4.

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AbstractMethane content in a coal seam is a necessary parameter for evaluating coal bed gas, and it poses an environmental risk to underground coal mining activities. Keeping in pace with comprehensive studies of coal bed gas, 12 coal samples were selected from the Sitarampur block of Raniganj Coalfield for analysis. The Petrographic examination illustrated that significant values of reactive macerals present in samples demonstrate that organic matter is dominated by the prominent source of aromatic hydrocarbons with a minor proportion of aliphatic hydrocarbon, which falls in the region of (Type III) kerogen, confirms the suitability for the potential of hydrocarbon generation. “A” factor (aliphatic/aromatic bands) and “C” factor (carbonyl/carboxyl bands) value concluded that the sample has the lowest aromaticity and the highest hydrocarbon-generating potential, which was also validated by the Van Krevelen diagram. The Van Krevelen diagram plots between the H/C and O/C ratio indicate that coal samples lie in the type III kerogen, and bituminous coal (gas prone zone) is present in the block, which is confirmed by the cross-plot between desorbed and total gas (cc/g). The in situ gas content values are high enough to produce methane from coal beds. The overall study concludes that the Sitarampur block from Raniganj Coalfield is suitable for hydrocarbon generation and extraction.

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Journal articles on the topic 'Aliphatic and aromatic hydrocarbons'

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