A detailed chemical study has been made on a suite of 27 Australian coals of varying rank. The coals had a wide range of H/C values and, in addition to chemical analysis, were examined by Fourier transform infrared spectroscopy and 13C solid state n.m.r. The coals were reacted with hydrogen in tetralin at 405°C and in decalin under nitrogen at 320°C. The products of these reactions were examined by a variety of spectroscopic and other analytical techniques. On the basis of the results it is proposed that brown coals consist of a polymeric lignin-based structure which traps varying amounts of smaller, more aliphatic, molecules. Black coals have more complex structures.
- liquefaction potential
- physical characterization