The laws of thermal degradation of the mixture of the heavy fraction of low-temperature coal tar and coal shale were investigated using dynamic thermogravimetry. The kinetic characteristics of the process were determined using various methods, including the Ozawa–Flynn-Wall, Friedman, non-parametric kinetics and Šesták–Berggren methods. It is shown that coal shale initiated changes in the kinetic parameters and decomposition rate of the heavy fraction of coal tar. It was found that a 13% content of coal shale in the mixture led to the maximum rate of weight loss of the heavy fraction of coal tar. A hydrodemetallization kinetic model of the mixture of the heavy fraction of low-temperature coal tar and coal shale is proposed. The kinetic parameters of the hydrodemetallization process were determined; in addition, the rate constants at various temperatures were estimated. The study shows that the distribution of trace elements in the hydrogenate from the initial mixture and in the hydrogenate from the solid residue was characterized by relatively low values of reaction rate constants. The maximum microelement distribution rate was achieved in the hydrogenate solid residue. Energy indicators of activation processes indicated that hydrodemetallization at low temperatures is advantageous from an energy point of view.

In this work, the kinetics of the redistribution of oils, resins, and asphaltenes in high-viscosity oil from the Karazhanbas field (Republic of Kazakhstan) were investigated. This was achieved with an ultrasonic treatment (22 kHz, 50 W) in the presence of a zeolite catalyst (1.0 wt%). The parameters of the technological process were established as a temperature range from 30 to 70 °C and an exposure time of 3 to 11 min. This allowed us to increase the oil content by 14.8% and decrease the concentration of resins by 12.2% and asphaltenes by 2.6%. Conversion schemes (“oils ↔ resins” and “resins ↔ asphaltenes”) were developed, which made it possible to determine the main direction of the reaction processes. The most rapid process is the conversion of resins to oils (k₂ = 0.1148–0.1860 min⁻¹). The process of the cracking of asphaltenes with the formation of resins (k₄ = 0.1023–0.1413 min⁻¹) ranks second in rates. Condensation reactions, including the transition of oils to resins (k₁ = 0.0175–0.0252 min⁻¹) and resins to asphaltenes (k₃ = 0.0139–0.0194 min⁻¹), occur significantly more slowly. The calculated activation energies (7.0–10.4 kJ/mol) show that the cavitation treatment of high-viscosity oil in the presence of a catalyst effectuates the processing of heavy oil with minimal energy consumption. A group composition analysis of the light and middle oil fractions demonstrated an increase in paraffinic, naphthenic, benzenic, and olefinic hydrocarbons, with a simultaneous decrease in naphthalenes and heteroatomic compounds. The results obtained confirm the effectiveness of ultrasonic–catalytic treatment for the structural cracking of high-viscosity oil and the formation of lighter hydrocarbon fractions.

The study investigates the kinetics of redistribution of oils, resins, and asphaltenes in high-viscosity oil from the Karazhanbas field during ultrasonic treatment (22 kHz, 50 W) in the presence of a zeolite catalyst (1.0% by mass). The parameters of the technological process - temperature range from 30 to 70°C, exposure time from 3 to 11 min - were established, which lead to an increase in oil content (by 14.8%), and a decrease in the concentration of resins (by 12.2%) and asphaltenes (by 2.6%). An increase in the conversion rate between oil components is observed until the 7th minute of treatment. Group analysis of light and medium oil fractions showed an increase in the content of paraffinic, naphthenic, benzene and olefinic hydrocarbons while reducing the proportion of naphthalenes and heteroatom compounds. The results obtained confirm the effectiveness of ultrasonic-catalytic treatment for the structural destruction of high-viscosity oil and the formation of lighter hydrocarbon fractions.

The paper investigates the effect of ultrasonic cavitation, in combination with catalysts, on the fractional composition of high-viscosity oil. Ultrasonic treatment was carried out at a frequency of 22 kHz and a power of 50 W for 10 min in the presence of HY-zeolite, NiFe/Y-zeolite and NiFe/microsphere (1 wt%) catalysts. Results showed that ultrasonic treatment without a catalyst leads to a reduction in the yield of the target distillate fractions. The HY-zeolite demonstrates the greatest efficiency, increasing the yield of the light fraction with a boiling point of up to 200 °C by 7.9% compared with the initial oil. The NiFe/zeolite and NiFe/microsphere catalysts contributed to the formation of naphthenic and aromatic structures in the light and middle fractions of high-viscosity oil; however, the yields of light fractions with a boiling point of up to 200 °C and at 200–300°C decreased.

Studies on the thermal destruction of a mixture of vacuum residue (tar) and primary coal tar (PCT) with and without Fe3O4and β-FeOOH catalytic additives, which were performed using...

Thermal behavior of low-temperature coal tar modified with two additives - 1% converter slag catalyst (Fe and Ti oxides) and 1% polyethylene was investigated. The purpose of the study was to determine the effect of double modification on the kinetics of thermal decomposition and the stability of the material. TG/DTG analysis showed that the modified coal tar decomposes predominantly via a one-step mechanism, with a peak decomposition rate at ~270 °C. Kinetic parameters calculated using the Coats–Redfern method indicated that the third-order reaction model best fits the data (R² = 0.996), with an activation energy of 42 kJ/mol. To improve accuracy, a non-parametric kinetics (NPK) method based on singular value decomposition (SVD) was applied, enabling isolation of the dominant decomposition stage and identification of reactive temperature zones. The kinetic behavior was also found to vary with heating rate due to changing contributions from secondary components. The results obtained demonstrate the high thermal activity and structural complexity of the modified tar, and also confirm the effectiveness of an integrated approach to the analysis of thermokinetics. The work can serve as a basis for the further development of fire-resistant, electrically insulating and carbon-based bonding materials with controllable characteristics.