Aliphatic Hydrocarbon Fractions Research Articles

Analisis Aspek Molekuler Biomarka Alkana Bercabang Core Badak 1/208 Muara Badak, Kutai Kartanegara, Kalimantan Timur

Study compound biomarka branched alkanes on core 1/208 Rhinos have done to contribute to the activities of oil exploration wells 1/208 Muara Badak Badak, East Kalimantan's Kutai Kartanegara-through core biomarka profile branched alkanes. Core samples extracted by alternately with solvent mixture of toluene-methanol (3: 1) and chloroform-methanol (3: 1). Then fractionated by Column Chromatography and Thin Layer Chromatography to obtain aliphatic hydrocarbon fraction. Fractions obtained were identified using Gas Chromatography-Mass Spectrometry.The content biomarka aliphatichydrocarbon fraction were identified, among others, iso and anteiso alkanes, mono and trimethyl alkanes. Compounds iso and anteiso alkanes, and alkyl alkane other, providing information that the source of organic material core samples I and II is derived from microorganisms prokaryotic or biogenic precursor derived from cyanobacteria (marine microorganisms) and homologous monomethyl alkanes found in core samples II closer homologous series monomethyl alkanes found in sediments and oil and Precambrian Proterozoic era, so it can be said that the core sample II core samples older than I.

Chromatographic study of the organic matter from Moroccan Rif bituminous rocks

The bituminous rocks of the Upper Cretaceous in the Moroccan Rif have been assessed and characterized in detail using organic geochemical techniques and a variety of organic geochemical parameters. The organic matter from 4 sites was studied in order to determine its thermal maturity and its depositional environments. The organic extracts (bitumens) were fractionated on silica-potassium hydroxide column according to the aliphatic hydrocarbons, acid compounds and polar compounds. Aliphatic hydrocarbons were identified by gas chromatography and mass spectrometry (GC/MS).The distribution of the aliphatic hydrocarbon fractions, and the various organic geochemical parameters (pristane/phytane, isoprenoids/n-alkanes, CPI, C27:C28:C29 regular, C2920S/(20S+20R), C29ββ/(ββ+αα), C29/C30 hopanes and Ts/Tm) showed that the studied samples were generally mature. Two of the 4 samples appeared to be derived from source rocks deposited under anoxic conditions while suboxic to oxic conditions seemed to have been dominant for the remaining two samples. Rock–Eval pyrolysis data in addition to GC results suggested types II, III and IV kerogens for the studied samples.

High frequency floral changes at the Paleocene–Eocene boundary revealed by comparative biomarker and palynological studies

The Cap d’Ailly area (Upper Normandy, France) shows several terrestrial–lagoonal sections recording the negative carbon isotope excursion (CIE) associated with the Paleocene–Eocene Thermal Maximum (PETM; 55.8Ma). A study of the biomarkers and spore/pollen content of the Vasterival section gave complementary information on paleofloral changes that occurred around the Paleocene–Eocene (P–E) boundary. Aliphatic hydrocarbon fractions revealed a high abundance of vascular plant biomarkers, including tricyclic diterpanes derived from conifers, fernenes derived from ferns and des-A-triterpenes derived from angiosperms. Whereas the vegetation of the depositional environment surroundings seemed alternately dominated by ferns and angiosperms (revealed from biomarkers), the regional flora seemed dominated strictly by angiosperms such as Juglandaceae (revealed by pollen). Spore/pollen assemblages revealed no major turnover in the paleovegetation, but slight variation in vegetation composition. However, both biomarkers and spores/pollen exhibited two intervals of rapid floral change: the first occurred around the P–E boundary and the second at the top of the strictly terrestrial unit that coincides with a marine transgression. Comparison of the data with published paleoclimatic results, obtained from the same samples, indicated that the first interval of floral change correlates with strong paleohydrological perturbations, whereas the second is linked to an increasing marine influence.

14C analysis of aliphatic hydrocarbon fractions from the hypersaline Lake Tyrrell, southeast Australia

Conventional biomarker studies typically interpret the distribution, structure and stable isotopic (e.g. 13C, D) composition of sedimentary hydrocarbons and polar compounds. However, compound and compound class specific 14C analysis (CSRA) is becoming increasingly relevant for characterising millennial scale residence and mobilisation of sedimentary organic carbon (OC). Here, the 14C content of the aliphatic and bulk fractions from shallow cores from the hypersaline playa, Lake Tyrrell, southeast Australia were compared. The aliphatic hydrocarbon fractions (predominantly n-alkanes) were substantially older than the corresponding bulk fractions, indicating the presence of active reservoirs of ancient carbon, likely derived from aeolian reworking of sediments. The 14C ages of the aliphatic hydrocarbons in the core revealed two noticeable shifts in age and source of ancient OC that were not apparent using biomarker composition and sedimentology alone. The study shows that aliphatic hydrocarbons are relatively simple to isolate, even from organically lean (ca. 0.05% TOC) terrestrial sediments, and their 14C ages yield information about carbon mobilisation and preservation not amenable to conventional analysis.

English

The recovery of an environment polluted by petroleum and allied hydrocarbons through bioremediation is being embraced globally as the best technology of removing hydrocarbon pollutants from environment. Infrared spectral changes and gravimetric analysis from the preliminary biodegradability study carried out on Agbabu Natural Bitumen showed the vulnerability of the bitumen to some bacteria: Pseudomonas putrefaciens, Pseudomonas nigrificans, Bacillus licheniformis, Pseudomonas fragi and Achromobacter aerogenes. This study investigates the ability of P. putrefaciens, P. nigrificans, B. licheniformis, P. fragi and A. aerogenes to degrade the aliphatic and polycyclic aromatic hydrocarbon fractions of Agbabu natural bitumen. Samples of the bitumen were separately inoculated with each of the bacteria for 14 days and the hydrocarbon profiles before and after inoculation were quantified using gas chromatography technique. The total aliphatic hydrocarbon compounds (C11 - C29) in the bitumen degraded by P. putrefaciens and P. nigrificans was slightly higher than that in the undegraded bitumen, while the concentration of compounds (C11 - C29) found in samples of the bitumen degraded by B. licheniformis, P. fragi and A. aerogenes was less than what was contained in the undegraded bitumen. Also the even-odd carbon-ratios of the degraded bitumen were higher than unity while these were less than unity in the undegraded bitumen. The polycyclic aromatic hydrocarbons (PAHs) profile in the bitumen degraded samples also differed from that of undegraded bitumen. A substantial reduction in the concentration of some PAHs was found in the bitumen samples following their degradation by the bacteria strains, typically from 55.98 to 30.79%, thus suggesting the possibility of using the bacteria strains for bioremediation process.   Key words: Agbabu, bitumen, bacteria, biodegradability, hydrocarbons. &nbsp

Biodegradation of diesel/biodiesel blends in saturated sand microcosms

The aim of the study was to evaluate the biodegradation extent of both aromatic and aliphatic hydrocarbon fractions in saturated sandy microcosm spiked with diesel/biodiesel blends (D, B10, B20, B30, B40, B50, B60, B70, B80, B90 and B100, where D is commercial petroleum diesel fuel and B is commercial biodiesel blend) augmented with a bacterial consortium of petroleum degraders. The biodegradation kinetics for blends were evaluated based on measuring the amount of emitted CO2 after 578days. Subsequently, the residual aromatic and aliphatic fractions were separated and determined by employing GC-FID and GC×GC–TOF-MS. Additionally, the influence of biodiesel-amendment on the community dynamics was assessed based on the results of real-time PCR analyzes. Our results suggest that the biodegradation extents of both aliphatic and aromatic hydrocarbon were uninfluenced by the addition of biodiesel, regardless of the concentration used. This observation leads to the conclusion that blending with biodiesel does not impact the long-term biodegradation of specific diesel oil fractions.

Evaluation of the organic matter sources using the δ13C composition of individual n-alkanes in sediments from Brazilian estuarine systems by GC/C/IRMS

The δ13C composition of individual n-alkanes (from C16 to C34) was measured from surface sediments of five Brazilian estuarine systems affected by different organic matter sources, such as harbor area, industries, urban centers and sugar cane crops, in order to determine the origins of the organic matter. The aliphatic hydrocarbon fraction was analyzed by gas chromatography–combustion–isotope ratio mass spectrometry (GC/C/IRMS). The levels of n-alkanes in the studied areas ranged from 0.34 to 18.14 μg kg−1, being relatively low in comparison to high polluted environments. The Carbon Preference Index (CPI) calculated in the C23–C34 range indicates that n-alkanes are mainly inherited from cuticular waxes of higher plants. The δ13C composition of all n-alkanes detected in the sediment samples ranged from −39.6 to −18.3‰ showing different sources for the studied estuarine systems. Through Principal Component Analysis (PCA) it was possible to verify the petrogenic influence in the n-alkane sources, especially in the Paraíba do Sul sediment samples. Differences up to 15‰ of the δ13C values between n-alkanes of odd and even carbon number (C26 and C27) also indicated mixture of petrogenic and biogenic sources in Paraíba do Sul River. High (less negative) δ13C n-alkane values of odd carbon number were obtained from two sampling sites located close to an ethanol plant, indicating residues discharge of sugar cane (C4 plant). Influence of C3 plants that are the main components of dense ombrophile forest was observed in the Itajaí-Açu sediments by the decrease of δ13C (about 10‰ compared to the Paraíba do Sul River δ13C).

Sources and distribution of aliphatic and polyaromatic hydrocarbons in coastal sediments from the Ushuaia Bay (Tierra del Fuego, Patagonia, Argentina)

The environmental quality of Ushuaia Bay, located at the southernmost tip of South America, is affected by the anthropogenic pressure of Ushuaia city. In this study, levels and sources of hydrocarbons in coastal sediments were assessed. Aliphatic hydrocarbon fractions ranged between 5.5 and 1185.3 μg/g dry weight and PAHs from not detected to 360 ng/g. Aliphatic diagnostic indices, the nalkanes homologous series occurrence, Aliphatic Unresolved Complex Mixtures (AliUCMs), and pristane and phytane isoprenoids indicated a petrogenic input. Some sites showed biogenic features masked by the anthropogenic signature. Particularly in port areas biodegradation processes were evident. PAH ratios showed a mixture of petrogenic and pyrogenic sources. Aliphatic and aromatic UCMs were strongly correlated, reflecting chronic pollution. Three areas were distinguished inside the bay: (1) east, with low hydrocarbons impact; (2) central, where hydrocarbons accumulation was related to source proximity and sediment characteristics; (3) south-west, where sediment characteristics and current circulation favour hydrocarbons accumulation.

Ecological development of Lake Donggi Cona, north-eastern Tibetan Plateau, since the late glacial on basis of organic geochemical proxies and non-pollen palynomorphs

Organic geochemical proxy data from surface sediment samples and a sediment core from Lake Donggi Cona were used to infer environmental changes on the northeastern Tibetan Plateau spanning the last 18.4 kyr. Long-chain n-alkanes dominate the aliphatic hydrocarbon fraction of the sediment extract from most surface sediment samples and the sediment core. Unsaturated mid-chain n-alkanes ( nC 23:1 and nC 25:1) have high abundances in some samples, especially in core samples from the late glacial and early Holocene. TOC contents, organic biomarker and non-pollen-palynomorph concentrations and results from organic petrologic analysis on selected samples suggest three major episodes in the history of Lake Donggi Cona. Before ca. 12.6 cal ka BP samples contain low amounts of organic matter due to cold and arid conditions during the late glacial. After 12.6 cal ka BP, relatively high contents of TOC and concentrations of Botryococcus fossils, as well as enhanced concentrations of mid-chain n-alkanes and n-alkenes suggest a higher primary and macrophyte productivity than at present. This is supported by high contents of palynomorphs derived from higher plants and algae and was possibly triggered by a decrease of salinity and amelioration of climate during the early Holocene. Since 6.8 cal ka BP Lake Donggi Cona has been an oligotrophic freshwater lake. Proxy data suggest that variations in insolation drive ecological changes in the lake, with increased aquatic productivity during the early Holocene summer insolation maximum. Short-term drops of TOC contents or biomarker concentrations (at 9.9 cal ka BP, after 8.0 and between 3.5 and 1.7 cal ka BP) can possibly be related to relatively cool and dry episodes reported from other sites on the north-eastern Tibetan Plateau, which are hypothesized to occur in phase with Northern Hemisphere cooling events.

Characteristics and source of inorganic and organic compounds in the sediments from two hydrothermal fields of the Central Indian and Mid-Atlantic Ridges

A combined inorganic and organic geochemical study was carried out on sediments collected from the Kairei hydrothermal field on the Central Indian Ridge (CIR) and the Logatchev hydrothermal field on the Mid Atlantic Ridge (MAR). Analysis of the major and trace elements as well as the minerals shows that the Kairei hydrothermal sediments are formed by the mixing of silica-rich hydrothermal fluids with Mg-rich seawaters, but the Logatchev sediments are associated with pelagic carbonate oozes containing some precipitates derived from hydrothermal plume fall-out. The rare earth element (REE) patterns of Kairei sediments show a character of light REE (LREE) enrichment and positive Eu anomaly, whereas two of the three Logatchev sediment samples lack positive Eu anomaly and have negative Ce anomaly. Patterns of aliphatic hydrocarbon fractions in the sediments from both hydrothermal fields exhibit high relative concentrations of volatile resolved components, smooth n-alkane distributions and high concentrations of the isoprenoids pristane and phytane. The composition of organic matter and C isotope composition of individual n-alkanes indicate that they come from marine photosynthetic autotrophs and hydrothermal organisms, as well as terrestrial inputs in the Kairei and the Logatchev hydrothermal fields. Several parameters of organic geochemistry, used for assessing the maturity of bitumen, are well correlated with one another. In general, these parameters indicate that the Kairei sediments are more mature than the Logatchev sediments. The relationship between the inorganic parameters (REE/Fe and Eu/Eu ∗) and the organic parameter (bitumen maturity) might reflect changes of the hydrothermal influence on the sediments. The results of this study provide an insight into the variation of inorganic and organic geochemistry in deep-sea hydrothermal systems.

Identification of C 24 and C 25 lanostanes in Tertiary sulfur rich crude oils from the Jinxian Sag, Bohai Bay Basin, Northern China

Unusual short chain lanostanes (C 24 and C 25) and C 30 lanostane were identified in sulfur rich crude oils from the Jinxian Sag, Bohai Bay Basin, northern China. Besides the regular steranes (C 27–30), a series of 4-methyl steranes (C 22−23, C 27−30), 4,4-dimethyl steranes (C 22−24, C 28−30), short chain steranes (C 23−26), abundant pregnanes (C 21−22) and androstanes (C 19−20), together with sulfur containing steroids (20-thienylpregnanes and thienylandrostanes) were detected in the aliphatic and branched-cyclic hydrocarbon fraction of these crude oils. A literature survey of some long chain sterane analogues (e.g., A-nor-steranes, norcholestanes, C 30 steranes, lanostanes) and pregnanes seems to point to a sponge and/or dinoflagellate source. 4-Methyl, 4,4-dimethyl steroids and lanosterols (4,4,14-trimethyl steroids as the basic skeleton of lanostanes) can be derived from methanotrophic bacteria. Thus, a biological origin from a prokaryotic methylotroph can be used to explain the common source of abundant short chain steranes (C 23–26), 4-methyl (C 22–23) and 4,4-dimethyl steranes (C 22–24), as well as lanostanes (C 24–25 and C 30 analogues) in our oil samples. Generally, the steroids appear to have been extensively sulfurized with sulfur substitution at the C-22 position in the side chain during the early stage of diagenesis, which was readily subject to attack by bacterial degradation (enzymatic cleavage) and/or abiotic oxidation. As a consequence, short chain sterane analogues (e.g., abundant pregnanes and androstanes in this study) and short chain lanostanes (C 24−C 25) might later be released through cleavage of weak C–S bonds at the C-22 carbon in the sulfurized steroids and lanostane sulfides. Finally, the formation of the short chain C 24−C 25 lanostanes and distinctive occurrence of short chain steranes in this study can be well explained by microbial biodegradation of sulfurized lanostanoids and steroids in the reservoir.

<b>Aliphatic and polycyclic aromatic hydrocarbons profiles of photomodified natural bitumen of Agbabu, Southwestern Nigeria</b>

The impact of sunlight on aliphatic and polycyclic aromatic hydrocarbons profiles of Agbabu natural bitumen in Nigeria was investigated. The raw flow type of the bitumen was purified and exposed to sunlight for six consecutive months. Different portions of the bitumen were withdrawn at an interval of one month and were separated into aliphatic and polycyclic aromatic hydrocarbon fractions by column chromatography, followed by the GC analyses of various fractions. The total aliphatic hydrocarbon content was found to be 485, 424, 416 and 392 g/kg for control, one, three and six months solar-irradiated bitumen samples, respectively; while the total polycyclic aromatic hydrocarbons content found in the control, one, three and six months solar-irradiated bitumen samples were 708, 733, 609 and 638 µg/g, respectively. The effects of sunlight on the compositional patterns of bitumen were discussed. KEY WORDS: Agbabu, Bitumen, Sunlight, GC, Aliphatic hydrocarbon, Polycyclic aromatic hydrocarbon Bull. Chem. Soc. Ethiop. 2010 , 24(3), 461-466.

Preferential utilization of petroleum oil hydrocarbon components by microbial consortia reflects degradation pattern in aliphatic–aromatic hydrocarbon binary mixtures

In this study, the abilities of two microbial consortia (Y and F) to degrade aliphatic–aromatic hydrocarbon mixtures were investigated. Y consortium preferentially degraded the aromatic hydrocarbon fractions in kerosene, while F consortium preferentially degraded the aliphatic hydrocarbon fractions. Degradation experiments were performed under aerobic conditions in sealed bottles containing liquid medium and n-octane or n-decane as representative aliphatic hydrocarbons or toluene, ethylbenzene or p-xylene as representative aromatic hydrocarbons (all at 100 mg/l). Results demonstrated that the Y consortium degraded p-xylene more rapidly than n-octane. It degraded toluene, ethylbenzene and p-xylene more rapidly than decane. In comparison, the F consortium degraded n-octane more rapidly than toluene, ethylbenzene or p-xylene, and n-decane more rapidly than toluene, ethylbenzene or p-xylene. 16S rRNA gene sequencing revealed that the Y consortium was dominated by Betaproteobacteria and the F consortium by Gammaproteobacteria, and in particular Pseudomonas. This could account for their metabolic differences. The substrate preferences of the two consortia showed that the aliphatic–aromatic hydrocarbon binary mixtures, especially the n-decane–toluene/ethylbenzene/p-xylene pairs, reflected their degradation ability of complex hydrocarbon compounds such as kerosene. This suggests that aliphatic–aromatic binary systems could be used as a tool to rapidly determine the degradation preferences of a microbial consortium.

Pollution source evaluation using petroleum and aliphatic hydrocarbons in surface sediments from two Brazilian estuarine systems

The levels of aliphatic hydrocarbons, including petroleum biomarkers (hopanes and steranes) were measured in surface sediments from two Brazilian estuarine systems affected by sugar cane monoculture and urbanization in order to identify their sources. The total aliphatic hydrocarbon fraction (TAH) concentration in the sediments ranged from 0.39 to 43.83 μg g −1 in the Mundaú–Manguaba estuarine-lagoon system and from 6.40 to 94.27 μg g −1 in the Paraiba do Sul River estuary. The levels of TAH in both study areas are relatively low. The carbon preference index (CPI) calculated for the C 23–C 34 range indicates that n-alkanes are mainly inherited from cuticular waxes of higher plants. However, the presence of hopanes and steranes indicates petrogenic input. The low values for the hopanes/ n-alkanes (Hop/ n-alk) and unresolved complex mixture (UCM)/ n-alk ratios indicate that the pollution is diluted with natural input.

Biomarker and compound-specific δ13C evidence for changing environmental conditions and carbon limitation at Lake Koucha, eastern Tibetan Plateau

A sediment core from Lake Koucha (eastern Tibetan Plateau) was investigated using organic biomarkers and their stable carbon isotope signatures. The correlation between TOC content, total amount of aquatic macrophyte-derived n-alkanes (e.g. nC23) and δ13C values of TOC and nC23 indicates that Lake Koucha was macrophyte-dominated before 8 cal ka BP. Shortly after the lake turned from a saline to a freshwater system at 7.2 cal ka BP, a variety of algal and bacterial markers such as hopanoids and isoprenoids emerged, of which phytane, pentamethylicosene (PMI), moretene and diploptene are particularly abundant. Phytane and PMI show different isotopic signals (≈−18 and ≈−28‰, respectively), which indicates that they originated from different sources. Phytane may have been derived from cyanobacteria, while methanogenic archaea may be the source of PMI. The isotopic depletion of diploptene and moretene (≈−60‰) indicates the presence of methanotrophs. After 6.1 cal ka BP, the saturated C20 highly branched isoprenoid (HBI) became the dominant constituent of the aliphatic hydrocarbon fraction. Such dominance has rarely been reported in lacustrine environments, and indicates a strong presence of algae (most likely diatoms) or cyanobacteria. At 4.7 cal ka BP, the appearance of an unsaturated C25 HBI, which is a specific biomarker for diatoms, was noted. Furthermore, the level of nC17-alkane was observed to increase in abundance in the uppermost two samples. These results suggest that the lake was phytoplankton-dominated during the last 6.1 ka. Relatively low biomarker concentrations and δ13C values at 6.0, 3.1 and 1.8 cal ka BP indicate the occurrence of cool periods, which is in agreement with inferences from other locations on the Tibetan Plateau. The δ13C values of nC23 range from −23.5 to −12.6‰, with high values at the peak of macrophyte abundance at ca. 11 cal ka BP and at the phytoplankton maximum between ca 6.1 and 2.8 cal ka BP. Thus, aquatic macrophyte-derived mid-chain n-alkanes have been found to be excellent indicators of carbon-limiting conditions, which lead to the assimilation of isotopically-enriched carbon species. The limitation of carbon sources could be a localized phenomenon occurring in dense plant stands (as in the older section of the core), or it may be induced by high primary productivity (as in the younger section). Since the δ13C value of the inorganic carbon source may vary, the offset between the δ13C values of nC23 and TIC could serve as a more precise proxy for carbon-limiting conditions in lacustrine environments, which could in turn be interpreted with respect to lacustrine paleo-productivity.

Characterization and Quantification of the Aliphatic Hydrocarbon Fraction during Linseed Development (Linum usitatissimum L.)

Changes in hydrocarbon composition were investigated during maturation of three varieties of linseed (H52, O116, and P129) cultivated in Tunisia. The hydrocarbon fraction of the three linseed oil samples was found to contain mainly n-alkanes and squalene. The greatest decrease of these components occurred between 7 and 21 days after flowering (DAF); thereafter, the changes were slight. At 7 DAF, P129 had a significantly higher level of squalene (27.24 mg/100 g of oil) than H52 (3.36 mg/100 g of oil), but from this date until 21 DAF squalene decreased much more actively in P129, resulting in similar levels in H52 (0.57 mg/100 g of oil) and P129 (0.52 mg/100 g of oil) at full maturity. In three varieties of linseed, 13 n-alkanes were detected ranging from C(22) to C(34) carbon atoms. The n-alkane composition of linseed oil was influenced by the ripening stage of seeds. At 7 DAF, C29 was the most predominant hydrocarbon (19.84 mg/100 g of total oil), followed by C(27) (11.82 mg/100 g) and C(25) (11.28 mg/100 g). C(29) exhibited the most significant decrease from 7 to 21 DAF, as a result C(27) being the most significant n-alkane component for the remainder of the period. At full maturity, the content of total n-alkanes in three varieties of linseed ranged from 4.0 to 4.26 mg/100 g of oil.

Application of geochemical parameters for characterization of oil samples using GC-MS technique

Geochemical characterization of eleven (11) oil samples has been carried out; using diagnostic biomarker parameters related to thermal maturity, organic matter source, age and depositional environment. Oleanane was only found in the Nigerian oil, serving as a primary feature in distinguishing it from other oils. All the oil samples appeared to have mixed organic matter input with samples of the same region closely related to each other based on the parameters measured. Biodegradation of some of the samples may have contributed to some of the observed variabilities. Key words: Biomarker, Oleanane, biodegradation, thermal maturity.

Linking chemical extraction to microbial degradation of 14C-hexadecane in soil

Chemical extractions have been shown to measure the biodegradable fraction of aromatic contaminants in soil; however, there is little research on the chemical prediction of aliphatic hydrocarbon degradation. The aim of this study was to investigate the potential for cyclodextrin extractions to predict hexadecane biodegradation in soil. Soils were amended with 10 or 100 mg kg(-1) of a model alkane n-hexadecane and 100 Bq g(-1) (14)C-n-hexadecane. Correlations between the extents of mineralisation and extractions of the (14)C-contaminant were determined. Solvent shake extractions and aqueous CaCl(2) extractions were poor predictors of hexadecane bioaccessibility. However, the novel HP-alpha-CD shake extraction showed close correlation (r(2)=0.90, n=36, p<0.05) to the mineralisation data. This novel extraction technique has the potential to be used to assess the biodegradable aliphatic hydrocarbon fraction in contaminated soils.

Compositional differences in biomarker constituents of the hydrocarbon, resin, asphaltene and kerogen fractions: An example from the Jet Rock (Yorkshire, UK)

Soluble and insoluble fractions of the Jet Rock sedimentary organic matter have been subjected to hydropyrolysis to evaluate their biomarker content. Hydropyrolysis is the temperature-programmed pyrolysis of organic matter in an open system fixed bed reactor under high hydrogen pressure in the presence of a sulfided molybdenum catalyst. The hydrocarbon products contain fossil lipids and biomarkers including high carbon number homologues and compounds with stereochemical configurations that are sensitive to exposure to high temperatures. Distinct differences exist between the concentrations and composition of biomarkers present in the different organic matter fractions. The sterane carbon number distribution, the dominant hopane carbon number and the proportions of tricyclic terpanes and extended tricyclic terpanes are different in each fraction, so biomarker parameters measured for different fractions are not directly comparable. The samples are of early oil window maturity and yet the quantities of biomarkers covalently bound into the kerogen fraction are of equal magnitude to the quantities that are present in the extractable aliphatic hydrocarbon fraction. However, the quantities of biomarkers in the polar resin and asphaltene fractions are two orders of magnitude lower and these two organic matter fractions contain biomarkers that are compositionally very different from the bulk of the biomarkers present in the total sedimentary organic matter. Isorenieratene derivatives were found in all fractions, indicating that green sulfur bacteria were present during sedimentation and that water column anoxia extended into the photic zone periodically if not continuously during the deposition of the Jet Rock.

05/01070 High-temperature air and steam gasification of densified biofuels

The aim of the study was to evaluate the biodegradation extent of both aromatic and aliphatic hydrocarbon fractions in saturated sandy microcosm spiked with diesel/biodiesel blends (D, B10, B20, B30, B40, B50, B60, B70, B80, B90 and B100, where D is commercial petroleum diesel fuel and B is commercial biodiesel blend) augmented with a bacterial consortium of petroleum degraders. The biodegradation kinetics for blends were evaluated based on measuring the amount of emitted CO2 after 578 days. Subsequently, the residual aromatic and aliphatic fractions were separated and determined by employing GC-FID and GC × GC–TOF-MS. Additionally, the influence of biodiesel-amendment on the community dynamics was assessed based on the results of real-time PCR analyzes. Our results suggest that the biodegradation extents of both aliphatic and aromatic hydrocarbon were uninfluenced by the addition of biodiesel, regardless of the concentration used. This observation leads to the conclusion that blending with biodiesel does not impact the long-term biodegradation of specific diesel oil fractions.