Vol 52, No 1 (2018)

The coals of different ranks from the Kuznetsk Coal Basin were studied by thermogravimetric analysis in inert and oxidizing atmospheres. Correlations between thermal decomposition characteristics [maximum decomposition temperatures (T_max, °C), maximum rates of decomposition (Vmax, %/min), and sample weight losses in different temperature ranges (Δm, %)] and proximate analysis [yields of volatile substances (Vdaf, %)] and petrographic analysis [vitrinite reflectance (R_o)] data and NMR-spectroscopic data [aromaticity factor ( fa)] as the characteristics of the degree of maturity of the test coals were established.

The methodologies of the determination of the free surface energy of solids were analyzed. It was shown that the currently available models for the calculation of free surface energy are based on the measurements of the angles of contact, and they contain an internal contradiction that consists in the fact that the surface energy is divided into two or three components: a polar component, hydrogen bonds, and a dispersion component. The free surface energy was calculated for the metamorphic series of coals from the Donets Basin (long-flame, gas, coke, and lean coals and anthracites) and graphites. Considerable differences in the values of free surface energy for different coalmine beds of anthracites were not revealed. Technical-grade and spectral graphites are insignificantly different from anthracites in terms of free surface energy, but a polar component of free surface energy has lower values of 0.0054–0.0117 J/m².

The effect of the hydrogenation temperature of oil shale from the Kashpir deposit on the yield and the properties of the resulting liquid hydrocarbons and gasoline and diesel fractions separated from them was studied. It was found that synthetic oil can be obtained from high-sulfur oil shale with the use of hydrogenation processing. In this case, it is possible to extract more than 90% of the organic matter of oil shale. Depending on the temperature of this processing, the sulfur content of the synthetic oil varied from 2.8 to 4.2 wt %, and the nitrogen and light fraction contents varied from 1.3 to 1.6 and from 34 to 67 wt %, respectively.

The composition of n-alkanes; sesqui-, di-, and triterpenoids; steroids; carboxylic acids; and tocopherols of sphagnum peat from the southern, middle, and northern taiga and forest-tundra of Western Siberia was studied by gas chromatography–mass spectrometry. It was shown that the latitudinal shift to the north leads to the preservation of the peat lipid components and sufficiently high values of carbon preference index (CPI) close to those of mire plants. This can be caused by a decrease in microbiological activity due to a decrease in the mean annual temperature. Towards the north, the total concentrations of n-alkanes, steroids, pentacyclic triterpenoids, squalene, and tocopherols increased, and a ratio of the total concentration of steroids to the concentrations of pentacyclic triterpenoids and hopanes decreased.

The kinetics of adsorption of the typical herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) and phenoxyacetic acid (the product of 2,4-D decay in the natural environment) on the activated carbon Sibunit was studied in an aqueous medium. The porosity and surface structure of the carbon were studied. The orders of 2,4-D and phenoxyacetic acid adsorption were determined. The high adsorption capacity of Sibunit for these substances was found.