Abstract
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.