1070-4272/02/7512-2021 $27.00 C 2002 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 75, No. 12, 2002, pp. 2021!2026. Translated from Zhurnal Prikladnoi Khimii, Vol. 75, No. 12, 2002,
Original Russian Text Copyright + 2002 by Platonov, D. Nikolaev, Sakharovskii, Proskuryakov, S. Nikolaev.
OF FOSSIL FUEL
H NMR Spectroscopy
of Organic Matter of Carbonate-Chara Sapropel
V. V. Platonov, D. S. Nikolaev, V. G. Sakharovskii, V. A. Proskuryakov, and S. G. Nikolaev
Lev Tolstoy State Pedagogical University, Tula, Russia
Skryabin Institute of Biochemistry and Physiology of Microorganisms, Pushchino, Moscow oblast, Russia
St. Petersburg State Technological Institute, St. Petersburg, Russia
Received July 3, 2002
Abstract-The structural-group composition of samples of organic matter of Chara sapropel and Characeae
algae was studied by
In investigation of bioliths, high-resolution NMR
spectroscopy was first used by Schnitzer and Barton
 to analyze the functional composition of soil hu-
mus extracts. This allowed identification of methyl,
polymethylene, phenolic, and carboxy groups in soil
humus. By now, a great body of information on frag-
mentary structure of organic fractions of lignites,
soils, shale oils, and bottom sediments has been de-
rived from the
H NMR spectra .
However, studies concerning structural organiza-
tion of various fragments of organic matter (OM) of
saprpels are fragmentary and devoted to humic acids
(HAs) only .
The aim of this work was to study the features
of structural-group composition of OM of carbonate-
chara sapropel and its main precursor, Characeae
algae, using high-resolution
H NMR spectroscopy.
Carbonate-chara sapropel samples for OM studies
were taken from Lake Bezdonka (Tula oblast) and
Characeae algae used by local balneal institutions.
To obtain comparative data, we recorded
spectra of HA samples recovered from valley peat
of the Yakhroma deposit (Moscow oblast) and mac-
rophyt sapropel from Lake Glubokoe (Republic of
Dry samples of HAs, fulvic acids (FAs), and
nonhydrolyzable residue, humin (H), were produced
from preliminary decalcified sapropel . A set of
[free] humic substances (FHSs) was recovered by ex-
traction of dry sapropel with a solution of deuterated
alkali immediately before recording the spectrum.
The hexane and alcoholic samples of macroalga,
Chara contraria L., were produced by extraction of
dry native mass in a Soxhlet apparatus. All the ex-
tracts were dried in a vacuum at a temperature not ex-
H NMR spectra were recorded on a WP-80SY
NMR spectrometer (Bruker, Germany) operating at
80 MHz with proton decoupling.
Samples for the
H NMR study were prepared by
dissolution in chloroform-d or in a solution of deu-
terated alkali in heavy water. The samples were sub-
jected to additional deuteration. For this purpose, the
solutions of the samples were dried in a vacuum on
a water bath at a temperature of approximately 90oC
to remove heavy water, with subsequent dissolution
of the dry residue in heavy water. The chemical shifts
H NMR spectra were measured relative to
the signals of the residual protons of deuterated sol-
vents: d 7.25 ppm for chloroform and d 5.00 ppm for
water at pH > 2.
The signals in the
H NMR spectra of the samples
were assigned according to .
The average length of alkyl radicals in the samples
was evaluated by analysis of the integral intensities
H NMR signals from methyl and methylene
groups. The average branching of alkyl radicals was
estimated from the relative content of methine groups.
The content of methylene and methine groups was