Experimental and Quantum Chemical Study on the Inhibition Characteristics of Glutathione to Coal Oxidation at Low Temperature.

In response to the frequent occurrence of coal spontaneous combustion accidents, this paper proposes to use glutathione (GSH) as an inhibitor to inhibit the coal oxidation at low temperature. Based on the gas production of oxidation, thermogravimetric analysis, electron spin resonance, and in situ Fourier infrared transform spectroscopy experiments, it is known that GSH has a good inhibiting effect on lignite, long-flame coal, and fatty coal. The optimal action temperature of GSH is 60-150 °C, which can effectively slow down the weight loss and exothermic process and reduce the gas production of CO and CO2. Compared with the raw coal, the GSH-treated coal samples possess higher crossing point temperature and lower reactive group content. Subsequently, quantum chemical calculations are performed using density functional theory. The results demonstrate that the inhibiting mechanism of GSH is inerting the reactive radicals in coal and converting them into more stable compounds. Meanwhile, the activation energy of the reaction between GSH and each reactive radical is small, and all of them can occur at room temperature and pressure. This study lays the groundwork for future development of inhibitors.