1070-4272/04/7701-0159C2004 MAIK [Nauka/Interperiodica]
Russian Journal of Applied Chemistry, Vol. 77, No. 4, 2004, pp. 159!161. Translated from Zhurnal Prikladnoi Khimii, Vol. 77, No. 4,
2004, pp. 163!165.
Original Russian Text Copyright + 2004 by Platonov, Kudrya, Proskuryakov.
OF FOSSIL FUEL
Chemical Structure of Asphaltene Compounds
from G17 Coal Semicoking Tar
V. V. Platonov, A. N. Kudrya, and S. V. Proskuryakov
Leo Tolstoy Tula State Pedagogical University, Tula, Russia
St. Petersburg State Technological Institute, St. Petersburg, Russia
Received July 3, 2002; in final form, June 2003
Abstract-The chemical structure of asphaltene compounds from the semicoking tar of coal belonging to the
G17 processing group was studied in detail.
Detailed data on the chemical composition of
semicoking tars formed under conditions excluding to
a maximal extent high-temperature pyrolysis furnish
information about the native structure of fragments
of coal organic matter (COM), their genetic relation-
ship with the initial biomaterial, and pathways of its
biogeochemical transformation in the course of coal
formation. Knowledge of the specific features of the
chemical structure of various COM components is
important for wide involvement of coals in production
of synthetic fuel, raw materials for organic and petro-
chemical synthesis, and metallurgical coke.
Asphaltenes (APs) are the least studied components
of tars formed by thermal degradation of coals, which
is due to relatively high molecular weight and poly-
functional composition of these compounds .
In this work we studied the chemical structure of
APs from the semicoking tar of G17 coal from the
Kuznetsk coal fields.
Characteristics of the coal: moisture content W
2.9, ash residue A
= 8.7, yield of volatiles V
36.6% of air-dry coal; elemental composition, %:
C 80.8, H 5.7, N 1.0, O 11.7, S
0.8. Yield of semi-
coking tar (% COM) 15.1; its chemical group compo-
sition, % of anhydrous tar: organic bases 1.15; car-
boxylic acids 0.85; phenols 18.96; hydrocarbons 32.9;
neutral oxygen-, nitrogen-, and sulfur-containing
compounds 25.11; asphaltenes 8.6; resinous sub-
stances and losses 12.43 .
AP characteristics: molecular weight M = 277.5;
elemental composition, %: C 77.8, H 8.2, N 2.6, O
11.4; functional composition, g-equiv mol
groups 0.42, quinoid groups 0.40, keto groups 0.27,
alcoholic groups 0.38, alkoxy groups 0.22, and hetero-
cyclic oxygen 0.76.
The IR spectra of APs contain bands (n,cm
the following fragments: aromatic rings (303033080,
1600, 1500, 144031465), with the increased intensity
of the bands at 1600 and 1500 suggesting the presence
of fused aromatic systems; CH
modes: 2840, 2940, 2925, 2850; bending modes:
7203740, 970, 1470), with the high intensity of these
bands suggesting high content of hydrogenated rings;
phenolic hydroxyls (358033670, 114031230, 13103
1410); methoxy (2850) and quinoid (1645, 1665,
1675, 1745) groups; cyclic and naphthenic alcohols
(103031120, 126031350, 363033700); oxygen- and
nitrogen-containing heterocycles (1565, 1500, 10153
1030, 8453870, 7403800).
Emission spectrum and X-ray fluorescence analyses
revealed the following elements in the AP mineral
matter: Fe, Mg, Al, Si, Ti, Ni, Sn, Sb, V, Mn, Cr, Zn,
Zr, Pt, Rh, Ge, Ga, Hg, Pb, Na, K, Ca, Co, and Nd.
The whole set of IR, UV3Vis, emission, and X-ray
fluorescence spectroscopic data and results of elemen-
tal, quantitative functional, and structural-group anal-
yses and cryoscopic measurements allows a conclu-
sion that the APs from G17 coal semicoking tar are
a complex mixture of compounds of high molecular
weight, containing various oxygen-containing func-
tional and alkyl groups and organometallic structures.
To examine the structure of AP components in
more detail, we separated APs into two fractions:
those soluble (1) and insoluble (2) in boiling acetone.
Fraction 1 after separation from fraction 2 was cooled
to room temperature and thus was separated into frac-