Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study
The thermal behavior of vanadyl porphyrins was studied by electron spin resonance during heating of kerogens, isolated from the La Luna (Venezuela) and Serpiano (Switzerland) bituminous rocks, at 250ºC for 1 to 20 days in the presence of air. During the thermal treatment of the kerogens, th...
Main Authors: | , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Serbian Chemical Society
2000-01-01
|
Series: | Journal of the Serbian Chemical Society |
Subjects: | |
Online Access: | http://www.doiserbia.nb.rs/img/doi/0352-5139/2000/0352-51390002113P.pdf |
id |
doaj-cf29a0b31bb64d27bd0b0623e24bc20d |
---|---|
record_format |
Article |
spelling |
doaj-cf29a0b31bb64d27bd0b0623e24bc20d2020-12-18T07:43:23ZengSerbian Chemical Society Journal of the Serbian Chemical Society0352-51391820-74212000-01-0165211312110.2298/JSC0002113P0352-51390002113PAir oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance studyPremović Pavle I.0Tonsa Ivana R.1Đorđević Dragan M.2Pavlović Mirjana S.3Faculty of Science, Department of Chemistry, Laboratory for Geochemistry and Cosmochemistry, NišFaculty of Science, Department of Chemistry, Laboratory for Geochemistry and Cosmochemistry, NišFaculty of Science, Department of Chemistry, Laboratory for Geochemistry and Cosmochemistry, NišVinča Institute of Nuclear Sciences, BelgradeThe thermal behavior of vanadyl porphyrins was studied by electron spin resonance during heating of kerogens, isolated from the La Luna (Venezuela) and Serpiano (Switzerland) bituminous rocks, at 250ºC for 1 to 20 days in the presence of air. During the thermal treatment of the kerogens, the vanadyl porphyrins resonance signals decrease monotonically and become quite small after 6 days of heating. Concomitantly, new vanadyl signals appear and, at longer heating times, dominate the spectrum. It is suggested that the secondary vanadyl species must have been formed from vanadyl porphyrins. Similar conversions of vanadyl porphyrins are observed under the same experimental conditions for asphaltenes extracted from the La Luna and Serpiano rocks, and floating asphalt from the Dead Sea (Israel). A comparison of the spin-Hamiltonian parameters for vanadyl porphyrins and the vanadyl compounds obtained during pyrolysis of the kerogens/asphaltenes suggests that the latter are of a non-porphyrin type. For comparison a study was conducted on Western Kentucky No. 9 coal enriched with vanadium (>400 ppm) from six mines. All the coal samples show only the presence of predominant by non-porphyrin vanadyl compounds, similar to those generated through laboratory heating of the kerogens/asphaltenes in air. In addition, some samples also contain a minor amount of vanadyl porphyrins.http://www.doiserbia.nb.rs/img/doi/0352-5139/2000/0352-51390002113P.pdfvanadyl porphyrinskerogenasphalteneincorporationelectron spin resonance |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Premović Pavle I. Tonsa Ivana R. Đorđević Dragan M. Pavlović Mirjana S. |
spellingShingle |
Premović Pavle I. Tonsa Ivana R. Đorđević Dragan M. Pavlović Mirjana S. Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study Journal of the Serbian Chemical Society vanadyl porphyrins kerogen asphaltene incorporation electron spin resonance |
author_facet |
Premović Pavle I. Tonsa Ivana R. Đorđević Dragan M. Pavlović Mirjana S. |
author_sort |
Premović Pavle I. |
title |
Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study |
title_short |
Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study |
title_full |
Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study |
title_fullStr |
Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study |
title_full_unstemmed |
Air oxidation of the kerogen/asphaltene vanadyl porphyrins: An electron spin resonance study |
title_sort |
air oxidation of the kerogen/asphaltene vanadyl porphyrins: an electron spin resonance study |
publisher |
Serbian Chemical Society |
series |
Journal of the Serbian Chemical Society |
issn |
0352-5139 1820-7421 |
publishDate |
2000-01-01 |
description |
The thermal behavior of vanadyl porphyrins was studied by electron spin
resonance during heating of kerogens, isolated from the La Luna (Venezuela)
and Serpiano (Switzerland) bituminous rocks, at 250ºC for 1 to 20 days in
the presence of air. During the thermal treatment of the kerogens, the
vanadyl porphyrins resonance signals decrease monotonically and become quite
small after 6 days of heating. Concomitantly, new vanadyl signals appear
and, at longer heating times, dominate the spectrum. It is suggested that
the secondary vanadyl species must have been formed from vanadyl porphyrins.
Similar conversions of vanadyl porphyrins are observed under the same
experimental conditions for asphaltenes extracted from the La Luna and
Serpiano rocks, and floating asphalt from the Dead Sea (Israel). A
comparison of the spin-Hamiltonian parameters for vanadyl porphyrins and the
vanadyl compounds obtained during pyrolysis of the kerogens/asphaltenes
suggests that the latter are of a non-porphyrin type. For comparison a study
was conducted on Western Kentucky No. 9 coal enriched with vanadium (>400
ppm) from six mines. All the coal samples show only the presence of
predominant by non-porphyrin vanadyl compounds, similar to those generated
through laboratory heating of the kerogens/asphaltenes in air. In addition,
some samples also contain a minor amount of vanadyl porphyrins. |
topic |
vanadyl porphyrins kerogen asphaltene incorporation electron spin resonance |
url |
http://www.doiserbia.nb.rs/img/doi/0352-5139/2000/0352-51390002113P.pdf |
work_keys_str_mv |
AT premovicpavlei airoxidationofthekerogenasphaltenevanadylporphyrinsanelectronspinresonancestudy AT tonsaivanar airoxidationofthekerogenasphaltenevanadylporphyrinsanelectronspinresonancestudy AT đorđevicdraganm airoxidationofthekerogenasphaltenevanadylporphyrinsanelectronspinresonancestudy AT pavlovicmirjanas airoxidationofthekerogenasphaltenevanadylporphyrinsanelectronspinresonancestudy |
_version_ |
1724378602324099072 |