Whole Process Inhibition of a Composite Superabsorbent Polymer-Based Antioxidant on Coal Spontaneous Combustion

Abstract

To achieve multiple and highly effective inhibition of coal spontaneous combustion, a novel composite inhibitor was developed by mixing a superabsorbent polymer (SAP) hydrogel with a synergistic antioxidant. Temperature-programmed oxidation, differential scanning calorimetry, and electron spin resonance were used to examine the inhibitor-treated coal samples to investigate the slowing effect of the composite inhibitor by comparing the inhibitions of the SAP hydrogel, synergistic antioxidant, and composite inhibitor on coal oxidation. The SAP hydrogel physically suppresses coal oxidation during the low-temperature phase, while the synergistic antioxidant chemically inhibits the oxidation during the high-temperature stage. Nevertheless, the composite inhibitor provides stable physicochemical inhibition for coal oxidation throughout the oxidation process by the synergistic effect of physical and chemical inhibition; the composite inhibitor provides a better overall effect for suppressing coal spontaneous combustion by combining the inhibiting characteristics of the SAP hydrogel and synergistic antioxidant. This study combines physical and chemical inhibitions of coal oxidation and provides a new method to efficiently prevent coal spontaneous combustion.