Coal aromaticity

Figure L Proposed cross-linked structure in coals Aromatic ring cluster ( 3) connecting bond (—) tetra functional cross-link (A) multifunctional crosslink (B).

BERKOWITZ Coal Aromaticity ir Average Molecular Structure... 

Fourier transform IR (FTIR) spectroscopy (54), which offers major benefits over conventional IR spectroscopy from greater sensitivity, spectral resolution, and substantially better signal-to-noise ratios, seems capable of furnishing equally good estimates of C /C and H /H (55). In this case, one measures Hal, derives from the stoichiometric relationship H /C = 1.8, and calculates Car by difference. However, applied to coal (as distinct from certain coal derivatives), FTIR spectroscopy has been mainly used to obtain better data for substituent functions (56, 57) and what are currently deemed to be the most authoritative data on coal aromaticity have all been recorded by 13C NMR spectroscopy. 

Solomon, P.R. 1981. Relation between coal aromatic carbon concentration and proximate analysis fixed carbon. Fuel, 60 3. 

VanderHart, D.L., and Retcofsky, H.L. Estimation of coal aromaticities by proton-decoupled carbon-13 magnetic resonance spectra of whole coals. 1976 55 202-204. 

---