COMBINED NMR AND FISCHER ASSAY STUDY OF OIL-SHALE CONVERSION

The conversion behaviour of 10 oil shales from worldwide deposits has been studied by combining solid- and liquid-state n.m.r. measurements with material balance Fischer assay conversion data. The extent of aromatization of aliphatic carbons was determined. Between 0 and 42% of the raw shale aliphatic carbon formed aromatic carbon during Fischer assay. For three of the shales, there was more aromatic carbon in the residue after Fischer assay than in the raw shale indicating that these shales had a greater tendency to coke during Fischer assay. Between 10 and 20% of the raw shale aliphatic carbons ended up as aliphatic carbons on the spent shale. Good correlations were found between the raw shale aliphatic carbon and carbon in the oil and between the raw shale aromatic carbon and aromatic carbon on the spent shale. Simulated distillations and molecular weight determinations were performed on the shale oils. More than 50% of the oil consisted of the atmospheric and vacuum gas oil boiling fractions.