HIGH-TEMPERATURE H-1-NMR STUDY OF COAL AND PITCH AT THE EARLY STAGES OF CARBONIZATION

The temperature dependence of the 1H-NMR absorption in coals and pitches have been obtained using a pulsed Fourier transform NMR spectrometer with a high temperature probe. The samples as received were heated in the high temperature probe and NMR spectra were obtained simultaneously. With increasing temperature, the value of the line width at half-height (ΔH 1 2) of a brown coal decreases and then increases rapidly. On the other hand, tar pitch and the γ component of a coal indicate that the values of ΔH 1 2 remain small over a wide temperature range. It is found that there is an excellent relation between the temperature dependence of ΔH 1 2 and the optical texture of the mesophase. © 1979.