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R. Marc Bustin - One of the best experts on this subject based on the ideXlab platform.
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Micro-FTIR spectroscopy of Liptinite Macerals in coal
International Journal of Coal Geology, 1998Co-Authors: R. Marc BustinAbstract:Abstract Reflectance FTIR microspectroscopy has been used to investigate the chemical structure of the Liptinite Macerals, alginite, bituminite, sporinite, cutinite and resinite in bituminous coals of Carboniferous to Tertiary age. In comparison with the spectra of vitrinite in the same coals, the micro-FTIR spectra of Liptinite Macerals are characterized by stronger aliphatic CH x absorptions at 3000–2800 and 1460–1450 cm −1 , less intense aromatic CC ring stretching vibration and aromatic CH out of plane deformation at 1610–1560 and 900–700 cm −1 respectively and various intense acid CO group absorptions at 1740–1700 cm −1 . The peaks at 1000–900 cm −1 due to aliphatic CH 2 wagging vibrations in olefins and at 730–720 cm −1 due to CH 2 rocking vibration in long chain aliphatic substances ([CH 2 ] n , n ≥4), are characteristic of Liptinite Macerals. Collectively the micro-FTIR spectral characteristics indicate that Liptinite is composed of greater numbers of long chain aliphatics, fewer aromatics and a broader range of oxygen-containing groups than other Macerals. Marked differences exist in micro-FTIR spectra within the Liptinite maceral group. Alginite has the strongest aliphatic and least aromatic absorptions followed by bituminite, resinite, cutinite and sporinite. The aliphatic components in alginite are the longest chained and least branched whereas those in sporinite are the shortest chained and most branched. Bituminite, resinite and cutinite are intermediate. Notable differences in micro-FTIR spectra of individual Liptinite Macerals, such as intensities and peak locations of aromatic CC in alginite, CO groups in bituminite and resinite and substituted aromatic CH and C–O–C groups in cutinite and sporinite, also exist, which are attributed to differences in depositional environments or biotaxonomy.
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Variation in the chemistry of Macerals in coals of the Mist Mountain Formation, Elk Valley coalfield, British Columbia, Canada
International Journal of Coal Geology, 1997Co-Authors: R. Marc BustinAbstract:Abstract Variations in elemental and molecular chemistry of Macerals, with vitrinite, semifusinite and sporinite in particular, are discussed for the coal seams of the Mist Mountain Formation in the Elk Valley coalfield, in western Canada. In the south Elk Valley coalfield, carbon content of vitrinite oscillates around 85%, and oxygen content increases gradually up section, from seam A to C. In the north Elk Valley coalfield, carbon content in vitrinite shows marked variations (from 70% to 85%) between the samples and is lower than in the south Elk Valley coalfield, which is consistent with a higher maturation level of south Elk Valley coalfield samples. Sulphur content is below 1% in both coalfields. Semifusinite, in general, has higher carbon and lower oxygen content than vitrinite, whereas cutinite has higher carbon content than vitrinite and slightly higher or comparable to that of semifusinite. Functional group distributions show large variations between the seams and these variations are attributed mainly to differences in a primary depositional environment and only occasionally to later weathering and oxidation processes. The results presented in this paper provide also information on the length and branching of aliphatic chains, which, for Liptinite Macerals is valuable from the oil generation viewpoint, whereas for semifusinite, it may help to understand reactive versus non-reactive behaviour during coking.
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Application of reflectance micro-Fourier transform infrared analysis to the study of coal Macerals: an example from the late jurassic to early cretaceous coals of the Mist Mountain Formation, British Columbia, Canada
International Journal of Coal Geology, 1996Co-Authors: R. Marc BustinAbstract:Abstract The applicability of the reflectance micro-Fourier Transform infra-red spectroscopy (FTIR) technique for analyzing the distribution of functional groups in coal Macerals is discussed. High quality of spectra, comparable to those obtained using other FTIR techniques (KBr pellet and transmission micro-FTIR), indicate this technique can be applied to characterizing functional groups under most conditions. The ease of sample preparation, the potential to analyze large intact samples, and ability to characterize organic matter in areas as small as 20 μm are the main advantages of reflectance micro-FTIR. The quantitative aspects of reflectance micro-FTIR require further study. The exaples from the coal seams of the Mist Mountain Formation, British Columbia show that at high volatile bituminous rank, reflectance micro-FTIR provides valuable information on the character of aliphatic chains of vitrinite and Liptinite Macerals. Because the character of aliphatic chains influences bond disassociation energies, such information is useful from a hydrocarbon generation viewpoint. In medium volatile bituminous coal Liptinite Macerals are usually not detectable but this technique can be used to study the degree of oxidation and reactivity of vitrinite and semifusinite.
Colin R. Ward - One of the best experts on this subject based on the ideXlab platform.
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mineralogy and organic petrology of oil shales in the sangkarewang formation ombilin basin west sumatra indonesia
International Journal of Coal Geology, 2009Co-Authors: Colin R. WardAbstract:Abstract The Ombilin Basin is filled by late Eocene to early Oligocene marginal fan deposits (Brani Formation) and lacustrine shales (Sangkarewang Formation), unconformably overlain by a late Oligocene to early Miocene fluvial sequence (Sawahlunto and Sawahtambang Formations) and capped by an early to mid-Miocene marine sequence (Ombilin Formation). Significant oil shale deposits occur in the Sangkarewang Formation, intercalated with thin laminated greenish-grey calcareous sandstones. X-ray diffraction shows that the sediments consist mainly of quartz, feldspar, carbonates and a range of clay minerals, together in some cases with minor proportions of sulphides, evaporites and zeolites. Feldspar and non-kaolinite clay minerals decrease up the sequence, relative to kaolinite, suggesting a changing sediment source as the basin was filled. Calcite, thought to be mainly of authigenic origin, is also more abundant in the middle and upper parts of the sequence. The organic matter in the oil shales of the sequence is dominated by Liptinite Macerals, particularly alginite (mainly lamalginite) and sporinite. Cutinite also occurs in some samples, along with resinite and traces of bituminite. The dominance of lamalginite in the Liptinite components suggests that the material can be described as a lamosite. Samples from the Sangkarewang Formation have vitrinite reflectance values ranging between 0.37% and 0.55%. These are markedly lower than the vitrinite reflectance for coal from the overlying Sawahlunto Formation (0.68%), possibly due to suppression associated with the abundant Liptinite in the oil shales. Fischer assay data on outcrop samples indicate that the oil yield is related to the organic carbon content. Correlations with XRD data show that, with one exception, the oil yield and organic carbon can also be correlated directly to the abundance of carbonate (calcite) and inversely to the abundance of quartz plus feldspar. This suggests that the abundance of algal material in the lake sediments was preferentially associated with carbonate deposition. High yields of oil are noted in some samples, as a percentage of the organic carbon content. This may indicate that partial generation of hydrocarbons from the material has already taken place, in association with thermal maturation of the Sangkarewang succession.
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variations in elemental composition of Macerals with vitrinite reflectance and organic sulphur in the greta coal measures new south wales australia
International Journal of Coal Geology, 2007Co-Authors: Colin R. Ward, Zhongsheng Li, Lila W. GurbaAbstract:Abstract The elemental composition of the individual Macerals in the Early Permian Greta Coal Measures of the northern Sydney Basin and adjoining Cranky Corner Basin, New South Wales, including some seams with high to very high organic sulphur contents, have been analysed in polished sections using light-element electron microprobe techniques, and the results evaluated in the light of vitrinite reflectance and other characteristics of the coals concerned. As with other Australian coals, the vitrinite Macerals in each sample have the lowest proportions of carbon and highest proportions of oxygen, and the inertodetrinite and fusinite Macerals the highest C and lowest O contents. Semifusinite and the Liptinite Macerals have intermediate C and O percentages. Organic sulphur and organic nitrogen are also highest in the vitrinite Macerals of the individual samples, and lowest in the fusinite and inertodetrinite components. The vitrinite Macerals in the Puxtrees seam of the Greta Coal Measures on the Muswellbrook Anticline, in the upper Hunter Valley, have similar elemental compositions (78% C) and similar reflectance values (Rv max around 0.7%) to vitrinites in the Late Permian bituminous coals in other parts of the Sydney-Bowen Basin. The vitrinites in the seams of the Cranky Corner Basin also have similar carbon contents to the Puxtrees seam material, suggesting a similar rank level, but have much lower vitrinite reflectance values (Rv max = 0.4–0.5%), probably due to marine influence associated with the depositional system. The vitrinites in the Greta seam on the Lochinvar Anticline, in the Lower Hunter region, have higher carbon contents (83%) than the Puxtrees material, suggesting a higher rank level, but similar to lower vitrinite reflectance values (Rv max = 0.6–0.7%). Vitrinite carbon is also constant through the seam profile, despite upwardly decreasing reflectance values in the seam due to progressive increases in marine influence. The vitrinites in the upper Greta seam and the Cranky Corner Basin coals have high to very high organic sulphur contents, again probably due to marine influence on the depositional process. The vitrinites in the Cranky Corner Basin coals, which have particularly high organic sulphur contents, also have somewhat lower oxygen contents in relation to their carbon percentages than those of other Australian seams, suggesting that the additional organic sulphur has replaced oxygen in the Macerals' molecular structure. The Macerals, especially the vitrinites, in the coals with high organic sulphur and anomalously low vitrinite reflectance also have up to 0.5% Al and 1% Ca intimately associated with the organic matter. Similar organically associated inorganic elements are commonly found in lower-rank (e.g. sub-bituminous) coals, but are usually lost from the organic matter at higher rank levels. The coals of the Greta Coal Measures therefore have vitrinite carbon contents consistent with a high volatile bituminous rank, but those seams or parts of seams with high organic sulphur due to substantial marine influence appear to have preserved the vitrinite reflectance values and organically associated inorganic elements more typical of lower-rank, sub-bituminous materials.
Asha Lata Singh - One of the best experts on this subject based on the ideXlab platform.
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Demineralization Study of High-Ash Permian Coal with Pseudomonas mendocina strain B6-1: A Case Study of the South Karanpura Coalfield, Jharkhand, India
Energy & Fuels, 2018Co-Authors: Aniruddha Kumar, Alok Singh, Prakash K. Singh, Asha Lata SinghAbstract:This paper entails the results of demineralization carried out on Karanpura Gondwana coals having high ash (30.57–21.80%) and low sulfur (0.29–0.20%) contents. The coal samples were subjected to demineralization using Pseudomonas mendocina strain B6-1, and the effect of various parameters, such as pH, temperature, incubation time, and pulp density, was observed. Optimum values of demineralization were found at pH 6.0, temperature of 35 °C, 6.0% (w/v) pulp density, and incubation time of 7 days. Reduction in the mineral matter (mean of 13.72–29.10%) content led to a relative increase in vitrinite, inertinite, and Liptinite Macerals. Further, the treatment has also caused an increase in the useful heat value, gross calorific value, and net calorific value of coal from 4824.86 to 5192.06 cal/g, from 5396.72 to 5647.47 cal/g, and from 5059.30 to 5273.80 cal/g (mean values), respectively. The method is eco-friendly and useful in obtaining clean fuel.
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experimental study on demineralization of coal with pseudomonas mendocina strain b6 1 bacteria to obtain clean fuel
Energy Exploration & Exploitation, 2014Co-Authors: Asha Lata Singh, Aniruddha Kumar, Prakash K. Singh, Akhilesh Kumar Yadav, Mahendra SinghAbstract:We present the results of the investigations carried out on the demineralization of coal of the Rajmahal Gondwana basin of India using Pseudomonas mendocina strain B6-1. Petrographically these coals are characterized by high concentration of inertinite Macerals with subordinate amount of vitrinite and Liptinite Macerals. The mineral matter content occurs in high concentration which gives a high ash yield. This coal contains relatively high content of major, minor and trace elements when compared with the Clarke values in coal.After the bacterial treatment a considerable reduction in the elemental content of oxygen, hydrogen and sulphur was seen. Reduction in the ash content (>5%) was achieved and variable degrees of removal of the various major, minor and trace element concentration was also noticed. Nearly 59% removal of Mn, 53% of Na, 13% of Fe was achieved among the major/minor elements while nearly 54% of As, 41% of Cd, 39% of Cu, 34% of Ni, 32% of Zn, 13% of Cr, 43% of Co and 66% of Pb could be remov...
A. C. Cook - One of the best experts on this subject based on the ideXlab platform.
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petroleum source rock assessment in non marine sequences pyrolysis and petrographic analysis of australian coals and carbonaceous shales
Organic Geochemistry, 1991Co-Authors: T. G. Powell, Nigel J Russell, M Smyth, Christopher J Boreham, A. C. CookAbstract:Abstract A series of Australian coals and terrestrial sediments ranging in age from Permian through tertiary have been analyzed to assess their petroleum source character and the suitability of various techniques for assessment of source rock potential in non-marine sequences. The procedures used include organic petrography, Rock-Eval pyrolysis, elemental analysis and quantitative pyrolysis-gas chromatography. The latter procedure was used to assess the potential yield of paraffins which is critical to the assessment of most non-marine source rocks. Principal components analysis was used to assist in the analysis of the data. Although the petroleum potential of the samples follows the broad trends in petrographic composition established for Australian coals, i.e. relative proportions of vitrinite, inertinite and Liptinite, there is much variation which cannot be explained petrographically at the maceral group level. Further, pyrolytic hydrocarbon yield is not related to overall elemental composition below an atomic H/C ratio of 1.0. The yield of phenols in flash pyrolysis is related to depositional setting as well as degree of maturation. The yield and carbon number distribution of normal hydrocarbons in flash pyrolysis varied widely depending on the age, nature and amount of Liptinite Macerals particularly in samples with Hydrogen Indices below 300. Liptinite-poor (
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petroleum source rock assessment in non marine sequences pyrolysis and petrographic analysis of australian coals and carbonaceous shales
Organic Geochemistry, 1991Co-Authors: T. G. Powell, Nigel J Russell, M Smyth, C J Oreham, A. C. CookAbstract:A series of Australian coals and terrestrial sediments ranging in age from Permian through tertiary have been analyzed to assess their petroleum source character and the suitability of various techniques for assessment of source rock potential in non-marine sequences. The procedures used include organic petrography, Rock-Eval pyrolysis, elemental analysis and quantitative pyrolysis-gas chromatography. The latter procedure was used to assess the potential yield of paraffins which is critical to the assessment of most non-marine source rocks. Principal components analysis was used to assist in the analysis of the data. Although the petroleum potential of the samples follows the broad trends in petrographic composition established for Australian coals, i.e. relative proportions of vitrinite, inertinite and Liptinite, there is much variation which cannot be explained petrographically at the maceral group level. Further, pyrolytic hydrocarbon yield is not related to overall elemental composition below an atomic H/C ratio of 1.0. The yield of phenols in flash pyrolysis is related to depositional setting as well as degree of maturation. The yield and carbon number distribution of normal hydrocarbons in flash pyrolysis varied widely depending on the age, nature and amount of Liptinite Macerals particularly in samples with Hydrogen Indices below 300. Liptinite-poor (< 10%) samples may yield significant amounts of hydrocarbons, but typically they have a low wax content. Sporinite-rich and liptodetrinite-rich samples give lower yields of normal hydrocarbons. These are predominantly of lower molecular weight. Suberinite and to a lesser extent cutinite are associated with high yields of waxy normal hydrocarbons, but some samples with high yields did not contain large amounts of these maceral. The correlation of Tmax to vitrinite reflectance varies with petrographic composition. The results have implications for the way source rock analyses are conducted and interpreted in non-marine sequences.
Wan Hasiah Abdullah - One of the best experts on this subject based on the ideXlab platform.
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source rock characteristics and hydrocarbon generation modelling of upper cretaceous mukalla formation in the jiza qamar basin eastern yemen
Marine and Petroleum Geology, 2014Co-Authors: Mohammed Hail Hakimi, Wan Hasiah AbdullahAbstract:Abstract The Upper Cretaceous Mukalla coals and other organic-rich sediments which are widely exposed in the Jiza-Qamar Basin and believed to be a major source rocks, were analysed using organic geochemistry and petrology. The total organic carbon (TOC) contents of the Mukalla source rocks range from 0.72 to 79.90% with an average TOC value of 21.50%. The coals and coaly shale sediments are relatively higher in organic richness, consistent with source rocks generative potential. The samples analysed have vitrinite reflectance in the range of 0.84–1.10 %Ro and pyrolysis T max in the range of 432–454 °C indicate that the Mukalla source rocks contain mature to late mature organic matter. Good oil-generating potential is anticipated from the coals and coaly shale sediments with high hydrogen indices (250–449 mg HC/g TOC). This is supported by their significant amounts of oil-Liptinite Macerals are present in these coals and coaly shale sediments and Py-GC (S 2 ) pyrograms with n -alkane/alkene doublets extending beyond nC 30 . The shales are dominated by Type III kerogen (HI One-dimensional basin modelling was performed to analysis the hydrocarbon generation and expulsion history of the Mukalla source rocks in the Jiza-Qamar Basin based on the reconstruction of the burial/thermal maturity histories in order to improve our understanding of the of hydrocarbon generation potential of the Mukalla source rocks. Calibration of the model with measured vitrinite reflectance (Ro) and borehole temperature data indicates that the present-day heat flow in the Jiza-Qamar Basin varies from 45.0 mW/m 2 to 70.0 mW/m 2 and the paleo-heat flow increased from 80 Ma to 25 Ma, reached a peak heat-flow values of approximately 70.0 mW/m 2 at 25 Ma and then decreased exponentially from 25 Ma to present-day. The peak paleo-heat flow is explained by the Gulf of Aden and Red Sea Tertiary rifting during Oligocene-Middle Miocene, which has a considerable influence on the thermal maturity of the Mukalla source rocks. The source rocks of the Mukalla Formation are presently in a stage of oil and condensate generation with maturity from 0.50% to 1.10% Ro. Oil generation (0.5% Ro) in the Mukalla source rocks began from about 61 Ma to 54 Ma and the peak hydrocarbon generation (1.0% Ro) occurred approximately from 25 Ma to 20 Ma. The modelled hydrocarbon expulsion evolution suggested that the timing of hydrocarbon expulsion from the Mukalla source rocks began from 15 Ma to present-day.
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petroleum source rock evaluation of the sebahat and ganduman formations dent peninsula eastern sabah malaysia
Journal of Asian Earth Sciences, 2013Co-Authors: Khairul Azlan Mustapha, Wan Hasiah AbdullahAbstract:The Sebahat (Middle Miocene to Early Pliocene) and Ganduman (Early Pliocene to Late Pliocene) Formations comprise part of the Dent Group. The onshore Sebahat and Ganduman Formations form part of the sedimentary sequence within the Sandakan sub-basin which continues offshore in the southern portion of the Sulu Sea off Eastern Sabah. The Ganduman Formation lies conformably on the Sebahat Formation. The shaly Sebahat Formation represents a distal holomarine facies while the sandy Ganduman Formation represents the proximal unit of a fluvial–deltaic system. Based on organic geochemical and petrological analyses, both formations posses very variable TOC content in the range of 0.7–48 wt% for Sebahat Formation and 1–57 wt% for Ganduman Formation. Both formations are dominated by Type III kerogen, and are thus considered to be gas-prone based on HI vs. Tmax plots. Although the HI–Tmax diagram indicates a Type III kerogen, petrographic observations indicate a significant amount of oil-prone Liptinite Macerals. Petrographically, it was observed that significant amounts (1–17% by volume) of Liptinite Macerals are present in the Ganduman Formation with lesser amounts in the Sebahat Formation. Both formations are thermally immature with vitrinite reflectance values in the range of 0.20–0.35%Ro for Ganduman Formation and 0.25–0.44%Ro for Sebahat Formation. Although these onshore sediments are thermally immature for petroleum generation, the stratigraphic equivalent of these sediments offshore are known to have been buried to deeper depth and could therefore act as potential source rocks for gas with minor amounts of oil.