Abstract
To investigate the mechanism of coal spontaneous combustion, distributions, evolutions, and oxidation characteristics of functional groups in different coals were characterized by employing in-situ FTIR, EPR, and TG/DSC-FTIR experiments. Experimental results indicated that -OH was the most active groups of coal spontaneous combustion. It not only could react with the absorbed oxygen spontaneously but also thebe the main product of the chemisorption. Consequently, -OH was believed to contribute most both for the loss and increase of coal massduring the process of spontaneous combustion. Aliphatic hydrocarbons were the main components to form -C-O-O• and could be further oxidized into C = O. However, reactions between aliphatic hydrocarbons and oxygen were non-spontaneous.EPR experiments suggested that the tendency of coal spontaneous combustion acutely depended on the stability and survival time of free radicals. The more stable and longer survival time of free radicals are, the lower tendency of coal spontaneous combustion is.
Oxidation Characteristics of Functional Groups in Relation to Coal Spontaneous Combustion
