Abstract
High temperature in-situ EPR studies has been carried out to investigate the change in paramagnetic species of coal up on heating. The spin concentration of coal during heating varied regardless of the thermoplastic properties of the coal. While, the peak-to-peak line width of EPR spectra closely correlated with the thremplasticity of coal, i.e. the line width of coking coal increased in the temperature range of thermoplasticity and decreased immediately in resolidification rage. The results indicate that the line width of EPR spectra could be a useful parameter to evaluate the thermoplastic and resolidification properties of coal.
