Том 51, № 4 (2017)

The overview is focused on methods for the processing of kinetic curves (with and without models). The paper demonstrates that the kinetics of thermochemical conversion of solid fuels can be described by a great number of kinetic processing methods, which lead to inconsistent estimates of kinetic coefficients. They give a rather simple approximation of experimental thermogravimetric curves. However, the kinetic triplet to be determined (activation energy, order of reaction, and preexponential factor) depends on the conditions of thermoanalytical studies and (to a greater extent) on the reactivity of the test fuels.

Some consequences of a known but insufficiently studied phenomenon, local heat generation in solid caustobioliths under near-surface conditions, when temperatures can be sufficient for the pyrolysis of organic matter (OM), the heating of underground waters, and even the melting of individual mineral components, were considered. A specific structural-deformation geofiltration medium (with the sections of thermally changed rocks and polygenetic breccias) is formed in the sections of the heating and burning (complete or partial) of caustobioliths, thermal conversion, and the deformations of host rock deposits. It was noted that increased permeability appears in not only thermally converted (pyrometamorphic) but also unchanged deposits (due to sagging, splitting, caving, and associated explosive degassing). The concepts of the possibility of these bodies to contain hydrocarbon components (of different genesis) at different depths. The results obtained can be useful in the forecast of the anthropogenic destabilization of the interior of the Earth due to waste storage and burial and the underground gasification of solid caustobioliths and in the studies of shale hydrocarbons.

The adsorption of 2,4-dichlorophenoxyacetic acid (2,4-D) as a typical herbicide from aqueous solutions on activated carbons prepared based on polyvinyl chloride by its alkaline dehydrochlorination and the subsequent heat treatment was studied. The structure of the activated carbon surface and the presence of functional groups on it were established. The kinetics of the process of adsorption was studied. The influence of activated carbon preparation conditions on the properties of the adsorbents was demonstrated.

The applicability of fallen leaves as a raw material for the production of solid briquette fuel was assessed. In the course of a laboratory study performed with the use of the raw material gathered within the city of Novosibirsk, test samples were obtained and their properties were characterized. A conclusion on the applicability of the new form of solid biofuel was made.

The interaction of coke coal with nitrosylsulfuric acid NOHSO₄ in acetonitrile at 20–25°C, times to 24 h, and the NOHSO₄/coal ratio R ≤ 50 mmol/g was studied. The process leads to the formation of oxysulfonated coal accompanied by an increase in the weight (to 46%), a decrease (by a factor of 3.8–7.3) in the concentration of radicals, and the formation of the following O-, S-, and N-containing groups in the coal structure: carboxyl, phenol, sulfo groups (≤1.9 mmol/g), and nitroso groups (≤0.9 mmol/g). Changes in the characteristics of oxysulfonated coal under varying R and upon hydrolysis were established by IR and EPR spectroscopy and elemental analysis. The results were interpreted within the framework of a mechanism that included the formation of coal radical cations as a result of electron transfer from coal to the nitronium cation, the intercalation of the bisulfate anion into the coal structure, and the nitrosation and sulfonation of coal arenes. Side oxidation reactions occurred simultaneously with the formation of carboxyl, phenol, and quinoid groups.