RELATIONSHIP OF COAL CHARACTERISTICS DETERMINED BY PYROLYSIS-GAS CHROMATOGRAPHY MASS-SPECTROMETRY AND NUCLEAR-MAGNETIC-RESONANCE TO LIQUEFACTION REACTIVITY AND PRODUCT COMPOSITION

Five coals, ranging in rank from subbituminous to high-volatile A bitu minous, were examined by C-13 NMR and flash pyrolysis gas chromatograp hy/mass spectrometry (Py-GC/MS). They were also subjected to liquefact ion in batch microautoclave reactors at three sets of conditions: 360 degrees C for 1 h in pyrene; 425 degrees C similarly; and temperature- programmed liquefaction for 15 min at 200 degrees C and 30 min at 425 degrees C in 9,10-dihydrophenanthrene with a sulfided molybdenum catal yst. Four of the five coals showed good relationships between the stru ctural fragments observed in Py-GC/MS and the dominant compound types in the hexane-soluble products from liquefaction at temperatures great er than or equal to 400 degrees C. For example, DECS 12 Pittsburgh sea m hvA bituminous coal showed a dominance of alkylnaphthalenes in the p yrogram, and this compound class was also dominant in the gas chromato gram of the hexane solubles. C-13 NMR showed a relationship of f(a)(H) to conversion of coal to liquids at 425 degrees C for 1 h. The combin ation of C-13 NMR and Py-GC/MS is useful for determining the probable light reaction products of direct Liquefaction. The correlations indic ate relationships between the compositions of the light fraction of th e liquefaction products and coal structural information. The combined characterization approach described here could be used for screening o f a nide suite of candidate feedstocks to winnow a few promising candi dates for detailed testing.