INTEGRATED USE OF DIRECT SOLID-STATE CHEMICAL PROBES FOR CHARACTERIZING THE CHEMICAL STRUCTURE OF COAL AND KEROGEN

摘要

and nitrogen forms to be directly speciated and quantified in carbonaceous solids. This information and carbon structural parameters obtained from solid-state 13C NMR provide a basis for developing average chemical structure models of coal and kerogen. By analyzing non-volatile pyrolysis products of peat, lignite and immature kerogen it is possible to infer the thermal chemistry pathways that are active during coalification and kerogen maturation. Moreover, it is possible to identify areas where non-thermal chemical pathways must be postulated for organic nitrogen and sulfur by reconciling observations from natural and laboratory matured samples. In the current study, new XPS, S-XANES and solid-state 13C NMR data from a bituminous coal maturity series and anthracite coals are analyzed together with published data for lignites and higher rank coals. These data are used to model coal and calculate the solubility parameter of coal as a function of rank.