TY  - CONF
AU  - Stojanović, Ksenija
AU  - Nytoft, Hans Peter
AU  - Kildahl-Andersen, Geir
AU  - Vuković, Nikola
PY  - 2018
UR  - https://ritnms.itnms.ac.rs/handle/123456789/823
AB  - A series of novel C33-C35 hexacyclic benzohopanes have been identified in coals and crude oils
of different ages from all over the world [1]. They differ from regular benzohopanes by the presence
of methyl group in position C-31. These compounds are more abundant in coals and terrestrial oils.
The investigation also showed that mature samples have distributions of benzohopanes distinct from
immature ones, which are characterised by a greater number of benzohopane isomers. Although exact
structures of the additional isomers were not determined, it seems they were formed by an
isomerisation of alkyl groups attached to the aromatic ring.
Two novel monoaromatic hydrocarbons (MW = 270; basic fragment ions m/z 255 and 146)
were identified in coals, mudstones and crude oils. Their structures were determined as cis- and transicetexa-
8,11,13-trienes (or dehydroicetexanes) using NMR spectroscopy. Dehydroicetexanes are
potential biomarkers of Cupressaceae (cypress conifers).
Benzo[b]naphtho[d]furans (BNFs) have been identified in oils, condensates, source-rocks,
coals and coaly shales, being more abundant in the latter. We detected BNFs (m/z 218) in relatively
high amounts in the aromatic fractions of pyrolysates of brown coals which attained the maturity
corresponding to vitrinite reflectance of 1.80 %Rr [2]. This result suggests that BNFs can be attractive
for investigations of mature fluids that originate from gas/condensate prone sources, rich in type III
kerogen, which are usually depleted in biomarkers. Recently, it was observed that [2,1]/[1,2]BNF
ratio can be used to describe lithofacies [3]. This ratio is much lower in sediments from fluvial-deltaic
systems than in clay-depleted sediments from marine environments.
1-Chloro-n-alkanes (m/z 91) have been identified in saltmarsh vegetation, recent sediments
from estuarine setting and freshwater lake sediments [4]. Despite their absence in the investigated
crude oils, we identified a series of 1-chloro-n-alkanes in pyrolysates of the corresponding
asphaltenes, obtained at 250 oC. This result indicates very good preservation of biomarkers occluded
inside asphaltenes and announces a possible application of 1-chloro-n-alkanes in correlation studies.
PB  - Tomsk : Institute of Strength Physics and Materials Science, Siberian Branch of Russian Academy of Sciences
PB  - Tomsk : Institute of Petroleum Chemistry, Siberian Branch of Russian Academy of Sciences
C3  - 10th International Conference „Oil and Gas Chemistry“
T1  - The review of some novel biomarkers in sedimentary organic matter
EP  - 673
SP  - 673
ER  - 

@conference{
author = "Stojanović, Ksenija and Nytoft, Hans Peter and Kildahl-Andersen, Geir and Vuković, Nikola",
year = "2018",
abstract = "A series of novel C33-C35 hexacyclic benzohopanes have been identified in coals and crude oils
of different ages from all over the world [1]. They differ from regular benzohopanes by the presence
of methyl group in position C-31. These compounds are more abundant in coals and terrestrial oils.
The investigation also showed that mature samples have distributions of benzohopanes distinct from
immature ones, which are characterised by a greater number of benzohopane isomers. Although exact
structures of the additional isomers were not determined, it seems they were formed by an
isomerisation of alkyl groups attached to the aromatic ring.
Two novel monoaromatic hydrocarbons (MW = 270; basic fragment ions m/z 255 and 146)
were identified in coals, mudstones and crude oils. Their structures were determined as cis- and transicetexa-
8,11,13-trienes (or dehydroicetexanes) using NMR spectroscopy. Dehydroicetexanes are
potential biomarkers of Cupressaceae (cypress conifers).
Benzo[b]naphtho[d]furans (BNFs) have been identified in oils, condensates, source-rocks,
coals and coaly shales, being more abundant in the latter. We detected BNFs (m/z 218) in relatively
high amounts in the aromatic fractions of pyrolysates of brown coals which attained the maturity
corresponding to vitrinite reflectance of 1.80 %Rr [2]. This result suggests that BNFs can be attractive
for investigations of mature fluids that originate from gas/condensate prone sources, rich in type III
kerogen, which are usually depleted in biomarkers. Recently, it was observed that [2,1]/[1,2]BNF
ratio can be used to describe lithofacies [3]. This ratio is much lower in sediments from fluvial-deltaic
systems than in clay-depleted sediments from marine environments.
1-Chloro-n-alkanes (m/z 91) have been identified in saltmarsh vegetation, recent sediments
from estuarine setting and freshwater lake sediments [4]. Despite their absence in the investigated
crude oils, we identified a series of 1-chloro-n-alkanes in pyrolysates of the corresponding
asphaltenes, obtained at 250 oC. This result indicates very good preservation of biomarkers occluded
inside asphaltenes and announces a possible application of 1-chloro-n-alkanes in correlation studies.",
publisher = "Tomsk : Institute of Strength Physics and Materials Science, Siberian Branch of Russian Academy of Sciences, Tomsk : Institute of Petroleum Chemistry, Siberian Branch of Russian Academy of Sciences",
journal = "10th International Conference „Oil and Gas Chemistry“",
title = "The review of some novel biomarkers in sedimentary organic matter",
pages = "673-673"
}

Stojanović, K., Nytoft, H. P., Kildahl-Andersen, G.,& Vuković, N.. (2018). The review of some novel biomarkers in sedimentary organic matter. in 10th International Conference „Oil and Gas Chemistry“
Tomsk : Institute of Strength Physics and Materials Science, Siberian Branch of Russian Academy of Sciences., 673-673.

Stojanović K, Nytoft HP, Kildahl-Andersen G, Vuković N. The review of some novel biomarkers in sedimentary organic matter. in 10th International Conference „Oil and Gas Chemistry“. 2018;:673-673..

Stojanović, Ksenija, Nytoft, Hans Peter, Kildahl-Andersen, Geir, Vuković, Nikola, "The review of some novel biomarkers in sedimentary organic matter" in 10th International Conference „Oil and Gas Chemistry“ (2018):673-673.

TY  - JOUR
AU  - Nytoft, H.P.
AU  - Vuković, Nikola
AU  - Kildahl-Andersen, Geir
AU  - Rise, Frode
AU  - Životić, Dragana
AU  - Stojanović, Ksenija
PY  - 2016
UR  - https://ritnms.itnms.ac.rs/handle/123456789/394
AB  - series of novel C-33-C-35 hexacyclic benzohopanes (C(33)b-C(35)b) were identified in 39 samples of coal extracts and 39 crude oils of different ages from all over the world. C(33)b and C(34)b homologues were isolated, and their structures were determined by nuclear magnetic resonance. The structure of C(35)b benzohopane was proposed based on the mass spectrum and its similarity with the mass spectra of structurally defined C(33)b and C(34)b homologues. The structures of the C(33)b-C(35)b hexacyclic benzohopanes are closely related to isohopanes; both groups are typical for terrestrial organic matter and can be useful in the correlation analysis. A possible pathway of formation of these novel benzohopanes and their hopanoid precursors with an additional branch in the aliphatic side chain is proposed. C(33)b-C(35)b hexacyclic benzohopanes are stable up to the maturity level corresponding to random vitrinite reflectance (Rr) of similar to 0.80%, which was demonstrated by analyzing the samples of different maturity and by the maturation simulation experiments: hydrous pyrolysis of two bituminous coals (Rr = 0.55 and 0.59%) and pyrolysis of an extracted bituminous coal (Rr = 0.56%) and its asphaltenes. This represents a confirmation that the formation of these novel benzohopanes is related to specific depositional conditions and microbial activity during diagenesis. Mature samples (Rr = 0.8%) and hydrous pyrolysate of the bituminous coals (Rr  LT  0.60%) obtained at 330 degrees C show a distinct distribution of benzohopanes in comparison to immature and moderately mature samples, which is characterized by a low abundance of the b series benzohopanes and the presence of regular and numerous other benzohopane isomers. The latter most likely represent isomers of regular and novel benzohopanes with different substitution patterns on the aromatic ring. This isomerization of alkyl groups attached to the aromatic ring, leading to the formation of thermodynamically more stable isomers, is a well-known maturation scenario so far reported in the series of alkylated naphthalenes, phenanthrenes, and dibenzothiophenes. Therefore, in the same way, a distribution of benzohopanes can indicate thermal maturity. In addition to the novel benzohopanes, three series (2 alpha, 2 beta, and 3 beta) of their methylated derivatives were identified in numerous samples. Finally, a novel C-35 heptacyclic benzohopane with an additional cyclopentane ring was also observed in the studied samples, and its structure was tentatively identified based on the mass spectrum. Opposite to the hexacyclic C(33)b-C(35)b benzohopanes, the formation of the C-35 heptacyclic benzohopane does not require a specific hopanoid precursor with two branches in the side chain. Therefore, this compound seems to have less geochemical significance than the new hexacyclic benzohopanes.
PB  - Amer Chemical Soc, Washington
T2  - Energy & Fuels
T1  - Identification of a Novel Series of Benzohopanes and Their Geochemical Significance
EP  - 5575
IS  - 7
SP  - 5563
VL  - 30
DO  - 10.1021/acs.energyfuels.6b00799
UR  - conv_765
ER  - 

@article{
author = "Nytoft, H.P. and Vuković, Nikola and Kildahl-Andersen, Geir and Rise, Frode and Životić, Dragana and Stojanović, Ksenija",
year = "2016",
abstract = "series of novel C-33-C-35 hexacyclic benzohopanes (C(33)b-C(35)b) were identified in 39 samples of coal extracts and 39 crude oils of different ages from all over the world. C(33)b and C(34)b homologues were isolated, and their structures were determined by nuclear magnetic resonance. The structure of C(35)b benzohopane was proposed based on the mass spectrum and its similarity with the mass spectra of structurally defined C(33)b and C(34)b homologues. The structures of the C(33)b-C(35)b hexacyclic benzohopanes are closely related to isohopanes; both groups are typical for terrestrial organic matter and can be useful in the correlation analysis. A possible pathway of formation of these novel benzohopanes and their hopanoid precursors with an additional branch in the aliphatic side chain is proposed. C(33)b-C(35)b hexacyclic benzohopanes are stable up to the maturity level corresponding to random vitrinite reflectance (Rr) of similar to 0.80%, which was demonstrated by analyzing the samples of different maturity and by the maturation simulation experiments: hydrous pyrolysis of two bituminous coals (Rr = 0.55 and 0.59%) and pyrolysis of an extracted bituminous coal (Rr = 0.56%) and its asphaltenes. This represents a confirmation that the formation of these novel benzohopanes is related to specific depositional conditions and microbial activity during diagenesis. Mature samples (Rr = 0.8%) and hydrous pyrolysate of the bituminous coals (Rr  LT  0.60%) obtained at 330 degrees C show a distinct distribution of benzohopanes in comparison to immature and moderately mature samples, which is characterized by a low abundance of the b series benzohopanes and the presence of regular and numerous other benzohopane isomers. The latter most likely represent isomers of regular and novel benzohopanes with different substitution patterns on the aromatic ring. This isomerization of alkyl groups attached to the aromatic ring, leading to the formation of thermodynamically more stable isomers, is a well-known maturation scenario so far reported in the series of alkylated naphthalenes, phenanthrenes, and dibenzothiophenes. Therefore, in the same way, a distribution of benzohopanes can indicate thermal maturity. In addition to the novel benzohopanes, three series (2 alpha, 2 beta, and 3 beta) of their methylated derivatives were identified in numerous samples. Finally, a novel C-35 heptacyclic benzohopane with an additional cyclopentane ring was also observed in the studied samples, and its structure was tentatively identified based on the mass spectrum. Opposite to the hexacyclic C(33)b-C(35)b benzohopanes, the formation of the C-35 heptacyclic benzohopane does not require a specific hopanoid precursor with two branches in the side chain. Therefore, this compound seems to have less geochemical significance than the new hexacyclic benzohopanes.",
publisher = "Amer Chemical Soc, Washington",
journal = "Energy & Fuels",
title = "Identification of a Novel Series of Benzohopanes and Their Geochemical Significance",
pages = "5575-5563",
number = "7",
volume = "30",
doi = "10.1021/acs.energyfuels.6b00799",
url = "conv_765"
}

Nytoft, H.P., Vuković, N., Kildahl-Andersen, G., Rise, F., Životić, D.,& Stojanović, K.. (2016). Identification of a Novel Series of Benzohopanes and Their Geochemical Significance. in Energy & Fuels
Amer Chemical Soc, Washington., 30(7), 5563-5575.
https://doi.org/10.1021/acs.energyfuels.6b00799
conv_765

Nytoft H, Vuković N, Kildahl-Andersen G, Rise F, Životić D, Stojanović K. Identification of a Novel Series of Benzohopanes and Their Geochemical Significance. in Energy & Fuels. 2016;30(7):5563-5575.
doi:10.1021/acs.energyfuels.6b00799
conv_765 .

Nytoft, H.P., Vuković, Nikola, Kildahl-Andersen, Geir, Rise, Frode, Životić, Dragana, Stojanović, Ksenija, "Identification of a Novel Series of Benzohopanes and Their Geochemical Significance" in Energy & Fuels, 30, no. 7 (2016):5563-5575,
https://doi.org/10.1021/acs.energyfuels.6b00799 .,
conv_765 .