TY  - JOUR
AU  - Pfendt, Petar A.
AU  - Polić, Predrag
AU  - Krsmanović, V. D.
AU  - Vitorović, Dragomir K.
PY  - 1990
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/4736
AB  - An attempt was made to distinguish metal-organic matter interactions in two types of sulfate-reducing environments, mild (MR) and strong sulfate-reducing (SR), in the Aleksinac oil shale deposit (Oligocene-Miocene). Samples from the MR group show (all differences are statistically highly significant): lower organic matter content, compared with the SR group, higher O/C and N/C ratios (0.147 ± 0.054 and 0.041 ± 0.014, respectively, compared with 0.125 ± 0.031 and 0.035 ± 0.008, respectively, in the SR group), and higher Cu, Zn, Pb, Cr, Mo and Co contents than in the SR group. Statistically significant correlations between metals, the N/C and the SiO2/Al2O3 ratio in the MR group only, represent a record of highly interdependent processes of organic-metal-silicate interactions which had been occurring in the mild sulfate-reducing conditions during oil shale formation.
PB  - Elsevier
T2  - Organic Geochemistry
T1  - Metal-organic matter interactions in the formation of an oil shale deposit
VL  - 16
IS  - 1-3
SP  - 621
EP  - 629
DO  - 10.1016/0146-6380(90)90075-B
ER  - 

@article{
author = "Pfendt, Petar A. and Polić, Predrag and Krsmanović, V. D. and Vitorović, Dragomir K.",
year = "1990",
abstract = "An attempt was made to distinguish metal-organic matter interactions in two types of sulfate-reducing environments, mild (MR) and strong sulfate-reducing (SR), in the Aleksinac oil shale deposit (Oligocene-Miocene). Samples from the MR group show (all differences are statistically highly significant): lower organic matter content, compared with the SR group, higher O/C and N/C ratios (0.147 ± 0.054 and 0.041 ± 0.014, respectively, compared with 0.125 ± 0.031 and 0.035 ± 0.008, respectively, in the SR group), and higher Cu, Zn, Pb, Cr, Mo and Co contents than in the SR group. Statistically significant correlations between metals, the N/C and the SiO2/Al2O3 ratio in the MR group only, represent a record of highly interdependent processes of organic-metal-silicate interactions which had been occurring in the mild sulfate-reducing conditions during oil shale formation.",
publisher = "Elsevier",
journal = "Organic Geochemistry",
title = "Metal-organic matter interactions in the formation of an oil shale deposit",
volume = "16",
number = "1-3",
pages = "621-629",
doi = "10.1016/0146-6380(90)90075-B"
}

Pfendt, P. A., Polić, P., Krsmanović, V. D.,& Vitorović, D. K.. (1990). Metal-organic matter interactions in the formation of an oil shale deposit. in Organic Geochemistry
Elsevier., 16(1-3), 621-629.
https://doi.org/10.1016/0146-6380(90)90075-B

Pfendt PA, Polić P, Krsmanović VD, Vitorović DK. Metal-organic matter interactions in the formation of an oil shale deposit. in Organic Geochemistry. 1990;16(1-3):621-629.
doi:10.1016/0146-6380(90)90075-B .

Pfendt, Petar A., Polić, Predrag, Krsmanović, V. D., Vitorović, Dragomir K., "Metal-organic matter interactions in the formation of an oil shale deposit" in Organic Geochemistry, 16, no. 1-3 (1990):621-629,
https://doi.org/10.1016/0146-6380(90)90075-B . .

TY  - JOUR
AU  - Vučelić, D.
AU  - Krsmanović, V.D.
AU  - Vučelić, V.
AU  - Kicanović, M.
AU  - Vitorović, Dragomir
PY  - 1990
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/4744
AB  - The chemical nature of the kerogen from Aleksinac (Yugoslavia) oil shale was studied by thermal analysis of a kerogen concentrate and the partially degraded kerogen concentrates obtained as intermediates in its stepwise alkaline permanganate oxidation. The initial kerogen concentrate decomposed in the range 200-550°C and the DTG profile consisted of several overlapping peaks. The partially degraded kerogen concentrates were thermally more stable. Their thermograms consisted of two distinct parts: the low- (150-420°C) and the high-temperature (420-650°C) part. Each of them was complex, involving two or more components. On the basis of IR data, it was suggested that the low-temperature part corresponded to the thermal degradation of aliphatic, and the high-temperature part to the degradation of aromatic components.
AB  - Mittels Thermoanalyse eines Kerogenkonzentrates und als Zwischenprodukte einer schrittweisen alkalischen Permanganatoxidation erhaltener, teilweise abgebauter Kerogenkonzentrate wurde die chemische Natur von Kerogen eines Ölschiefers aus Aleksinac (Jugoslawien) untersucht. Das ursprüngliche Kerogenkonzentrat zersetzt sich im Bereich 200–550°C, die DTG-Kurve besteht aus mehreren überlappenden Peaks. Die teilweise abgebauten Kerogenkonzentrate waren thermisch stabiler. Ihre Thermogramme gliedern sich in zwei Teile: in den Niedrig- (150–420°C) und in den Hochtemperaturbereich (420–650°C). Alle waren komplexer Natur, bestehend aus zwei oder mehr Komponenten. IR-sUntersuchungen lassen darauf schließen, daß der Niedrigtemperaturbereich dem thermischen Abbau der aliphatischen, der Hochtemperaturbereich hingegen dem Abbau der aromatischen Bestandteile entspricht.
PB  - Springer
T2  - Journal of Thermal Analysis
T1  - Thermoanalytical characterization of Aleksinac (Yugoslavia) oil shale kerogen
VL  - 36
IS  - 7-8
SP  - 2465
EP  - 2473
DO  - 10.1007/BF01913643
ER  - 

@article{
author = "Vučelić, D. and Krsmanović, V.D. and Vučelić, V. and Kicanović, M. and Vitorović, Dragomir",
year = "1990",
abstract = "The chemical nature of the kerogen from Aleksinac (Yugoslavia) oil shale was studied by thermal analysis of a kerogen concentrate and the partially degraded kerogen concentrates obtained as intermediates in its stepwise alkaline permanganate oxidation. The initial kerogen concentrate decomposed in the range 200-550°C and the DTG profile consisted of several overlapping peaks. The partially degraded kerogen concentrates were thermally more stable. Their thermograms consisted of two distinct parts: the low- (150-420°C) and the high-temperature (420-650°C) part. Each of them was complex, involving two or more components. On the basis of IR data, it was suggested that the low-temperature part corresponded to the thermal degradation of aliphatic, and the high-temperature part to the degradation of aromatic components., Mittels Thermoanalyse eines Kerogenkonzentrates und als Zwischenprodukte einer schrittweisen alkalischen Permanganatoxidation erhaltener, teilweise abgebauter Kerogenkonzentrate wurde die chemische Natur von Kerogen eines Ölschiefers aus Aleksinac (Jugoslawien) untersucht. Das ursprüngliche Kerogenkonzentrat zersetzt sich im Bereich 200–550°C, die DTG-Kurve besteht aus mehreren überlappenden Peaks. Die teilweise abgebauten Kerogenkonzentrate waren thermisch stabiler. Ihre Thermogramme gliedern sich in zwei Teile: in den Niedrig- (150–420°C) und in den Hochtemperaturbereich (420–650°C). Alle waren komplexer Natur, bestehend aus zwei oder mehr Komponenten. IR-sUntersuchungen lassen darauf schließen, daß der Niedrigtemperaturbereich dem thermischen Abbau der aliphatischen, der Hochtemperaturbereich hingegen dem Abbau der aromatischen Bestandteile entspricht.",
publisher = "Springer",
journal = "Journal of Thermal Analysis",
title = "Thermoanalytical characterization of Aleksinac (Yugoslavia) oil shale kerogen",
volume = "36",
number = "7-8",
pages = "2465-2473",
doi = "10.1007/BF01913643"
}

Vučelić, D., Krsmanović, V.D., Vučelić, V., Kicanović, M.,& Vitorović, D.. (1990). Thermoanalytical characterization of Aleksinac (Yugoslavia) oil shale kerogen. in Journal of Thermal Analysis
Springer., 36(7-8), 2465-2473.
https://doi.org/10.1007/BF01913643

Vučelić D, Krsmanović V, Vučelić V, Kicanović M, Vitorović D. Thermoanalytical characterization of Aleksinac (Yugoslavia) oil shale kerogen. in Journal of Thermal Analysis. 1990;36(7-8):2465-2473.
doi:10.1007/BF01913643 .

Vučelić, D., Krsmanović, V.D., Vučelić, V., Kicanović, M., Vitorović, Dragomir, "Thermoanalytical characterization of Aleksinac (Yugoslavia) oil shale kerogen" in Journal of Thermal Analysis, 36, no. 7-8 (1990):2465-2473,
https://doi.org/10.1007/BF01913643 . .

TY  - JOUR
AU  - Vitorović, Dragomir K.
AU  - Krsmanović, V. D.
AU  - Pfendt, Petar A.
PY  - 1980
UR  - https://cer.ihtm.bg.ac.rs/handle/123456789/4408
AB  - Two oxidizing agents were used for structural studies of the kerogen from Aleksinac shale (Yugoslavia), namely: (1) alkaline potassium permanganate, and (2) acidic ferric chloride. (1) The main goal with alkaline permanganate was to obtain optimum yields of identifiable oxidation products with preserved kerogen structural characteristics. In order to find optimal conditions, experiments were carried out at various temperatures (20-100°C) with varying amounts of permanganate per step. The best total yield of isolable degradation products (92,25%) was obtained at 75°C. At the same reaction temperature the best yield of ether-soluble acids was obtained (39% of the total organic matter). Kerogen degradation products obtained in high yields provide a better basis for more reliable structural interpretations than the products obtained in minor yields, which may represent small undefined portions of the original kerogen. (2) Ferric chloride is an oxidant of relatively high oxidation potential, although it is more gentle and more specific (e.g., dehydrogenation and decarboxylation) than most oxidation reagents containing oxygen used in kerogen structural studies. In oxidation of the Aleksinac shale kerogen concentrate with acidic ferric chloride solution, the pyrite content decreased (38-75%), and the kerogen content increased (7-15%). A small portion of the kerogen (∼8%) was degraded into soluble products. The chemical nature of the kerogen was considerably changed. In addition to a decrease in the atomic H C ratio and an increase in the O C ratio, changes in the content of aliphatic, aromatic, carbonyl and quinoid structures were observed.
PB  - Elsevier
T2  - Physics and Chemistry of the Earth
T1  - Kerogen structural studies-oxidations with alkaline permanganate and with ferric chloride
VL  - 12
IS  - C
SP  - 585
EP  - 589
DO  - 10.1016/0079-1946(79)90140-X
ER  - 

@article{
author = "Vitorović, Dragomir K. and Krsmanović, V. D. and Pfendt, Petar A.",
year = "1980",
abstract = "Two oxidizing agents were used for structural studies of the kerogen from Aleksinac shale (Yugoslavia), namely: (1) alkaline potassium permanganate, and (2) acidic ferric chloride. (1) The main goal with alkaline permanganate was to obtain optimum yields of identifiable oxidation products with preserved kerogen structural characteristics. In order to find optimal conditions, experiments were carried out at various temperatures (20-100°C) with varying amounts of permanganate per step. The best total yield of isolable degradation products (92,25%) was obtained at 75°C. At the same reaction temperature the best yield of ether-soluble acids was obtained (39% of the total organic matter). Kerogen degradation products obtained in high yields provide a better basis for more reliable structural interpretations than the products obtained in minor yields, which may represent small undefined portions of the original kerogen. (2) Ferric chloride is an oxidant of relatively high oxidation potential, although it is more gentle and more specific (e.g., dehydrogenation and decarboxylation) than most oxidation reagents containing oxygen used in kerogen structural studies. In oxidation of the Aleksinac shale kerogen concentrate with acidic ferric chloride solution, the pyrite content decreased (38-75%), and the kerogen content increased (7-15%). A small portion of the kerogen (∼8%) was degraded into soluble products. The chemical nature of the kerogen was considerably changed. In addition to a decrease in the atomic H C ratio and an increase in the O C ratio, changes in the content of aliphatic, aromatic, carbonyl and quinoid structures were observed.",
publisher = "Elsevier",
journal = "Physics and Chemistry of the Earth",
title = "Kerogen structural studies-oxidations with alkaline permanganate and with ferric chloride",
volume = "12",
number = "C",
pages = "585-589",
doi = "10.1016/0079-1946(79)90140-X"
}

Vitorović, D. K., Krsmanović, V. D.,& Pfendt, P. A.. (1980). Kerogen structural studies-oxidations with alkaline permanganate and with ferric chloride. in Physics and Chemistry of the Earth
Elsevier., 12(C), 585-589.
https://doi.org/10.1016/0079-1946(79)90140-X

Vitorović DK, Krsmanović VD, Pfendt PA. Kerogen structural studies-oxidations with alkaline permanganate and with ferric chloride. in Physics and Chemistry of the Earth. 1980;12(C):585-589.
doi:10.1016/0079-1946(79)90140-X .

Vitorović, Dragomir K., Krsmanović, V. D., Pfendt, Petar A., "Kerogen structural studies-oxidations with alkaline permanganate and with ferric chloride" in Physics and Chemistry of the Earth, 12, no. C (1980):585-589,
https://doi.org/10.1016/0079-1946(79)90140-X . .