Interaction of vitrinite and inertinite of Bulianta coal in pyrolysis

•The establishment of non-interacting system and interacting system.•An analysis of pyrolysis interaction between vitrinite and inertinite of coal. The interaction mechanism between vitrinite and inertinite during coal pyrolysis was investigated by the Fourier transfer-infrared (FT-IR) analysis, thermogravimetry (TG) analysis, and fixed-bed reaction analysis. The results indicated that different reactions were carried out under various reaction temperature range. Under the low-temperature pyrolysis scope of 300–350°C, the interaction between vitrinite and inertinite was ascribed to the combination of alkyl radical generated in the pyrolysis of vitrinite and inertinite. Under the pyrolysis temperature of 350°C, the polycondensation was monitored. Under the pyrolysis temperature range from 400 to 700°C, the hydrogen radical generated from the vitrinite realized aromatic hydrogenation reaction and side chain substitution reaction with inertinite. The condensation reaction, polycondensation and the higher level aromatization reaction also happened between the vitrinite and the inertinite while increasing the temperature. From 750 to 900°C, the aromatic dehydrogenation reaction happened in the vitrinite and inertinite.