Effect of electrochemical oxidation of pyrite on coal spontaneous combustion

Abstract

ABSTRACT In order to study the effect of electrochemical oxidation of pyrite in high-sulfur coal on coal spontaneous combustion, the electrochemical oxidation reaction of pyrite in coal was promoted by electrolysis experiments. The FTIR test results show that the content of active groups -OH and -CH2 increases after electrolysis of high sulfur coal. According to the ignition activation energy theory, which can determine the difficulty of spontaneous combustion of coal, the activation energy of coal samples before and after electrolysis was calculated by TG curve. The ignition activation energy of high-sulfur coal after electrolysis treatment is reduced to 0.85 times that of raw coal, and the ignition activation energy of low-sulfur coal remains basically unchanged. The electrochemical oxidation process of pyrite promotes the enhancement of coal polarization and promotes the development of reactive groups, thereby enhancing the activity of coal and promoting the spontaneous combustion of coal. In addition, compared with raw coal, the shortest ignition time of high sulfur coal after electrolysis was shortened by 14 hours, which indicates that the electrochemical oxidation process of pyrite effectively promoted the low temperature oxidation reaction of coal.