Study on the inhibition performance of double network physicochemical nanocomposite gel inhibitor on coal spontaneous combustion

To strengthen the inhibition effect of an inhibitor on spontaneous coal combustion throughout the process, this study used solution polymerization to synthesize hyaluronic acid and polyethylene glycol into a double network gel. The double network gel was grafted with a chemical inhibitor, epigallocatechin gallate, and polymerized with nanomaterial attapulgite to prepare a double network gel composite inhibitor with a whole-process inhibition effect. From the results of the scanning electron microscopy test, we found that the folds and pores on the surface of the inhibitor considerably increased with composite treatment. From the results of thermogravimetric analysis, it was proved that the average increase in each characteristic temperature point of the coal sample was 28.15%. According to the results of differential scanning calorimetry, it was found that the heat release interval of the inhibited sample was narrowed, and the total heat release was reduced by 2408.08 J/g. From the results of gas analysis, it was concluded that the production of CO, CO2, and CH4 by the inhibited sample markedly reduced, which verified the environmental friendliness of the inhibitor. Through a diffuse reflection infrared spectrum test, it was found that the inhibition treatment could deactivate the active groups in coal and increase the content of the ether bonds of the stable functional groups, which proved that the composite inhibitor is an excellent fire prevention material.