27Al and29Si SOLID STATE NUCLEAR MAGNETIC RESONANCE OF COAL AND HEAVY OIL - DERIVED MINERAL MATTER

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Abstract
Applications of solid state Al-27 and Si-29 nuclear magnetic resonance spectroscopy to the study of clay mineral/quartz derived from heavy oils/ bitumen and coals are discussed. Coal samples exhibiting different responses to flocculation in a coal washery were studied. Al-27 spectra obtained from both raw coals and their corresponding low temperature ashes (LTA) were nearly identical and consistent with x-ray diffraction analyses that indicated kaolinite and illite dominated the clay mineral fraction. Chemical shift and linewidth changes in the high temperature ashes were attributed to the transformation of octahedral aluminum sites to low symmetry, four and five coordinate, complexes. Recycle delay studies of the Si-29 spectra of the LTA's samples revealed little change over the range of 5 to 60 s. Major changes in high temperature ash spectra occurred over the same range of delay times and were attributed to the effects of dehydroxylation. Bitumen/heavy oil-derived solids were also studied as a function of processing history. Fractionation of the clay mineral/quartz components among the feeds, products and tails were monitored by Si-29 nmr. Recycle delay effects on the LTA's were investigated. Line broadening'due to increased concentrations of iron-containing minerals in some fractions was observed.