ABSTRACT
This chapter briefly reviews selected aspects of the evidence for, and techniques employed in identifying, the mobile component including solvent extraction, proton and carbon-13 nuclear magnetic resonance spectroscopy. It discusses the related aspects of these analyses and the relevance of such measurements to coal structure-property relationships. Macerals are organic substances, or optically homogeneous aggregates of organic substances, possessing distinctive physical and chemical properties. Many NMR measurements related to mass fraction analysis of multi-phase or multi-component systems rely on the determination of the number of decays observed in a relaxation time experiment. The solvent-soluble fraction has been considered responsible for solvation of the molecular units in coal as they become less rigid with thermal treatment.
