SMALL ANGLE; X-RAY SCATTERING FROM COAL-DERIVED LIQUIDS

Small anele Zrlids are complex mixtures of liquid and semi-liquid canstituents. They can be broadly classified as oils, resins, asphalknes and preasphaknes. Oils and resins are nominally soluble in pentane, asphaltenes are insoluble irl pentane but soluble in benzene or toluene and preasphaftenes are insoluble in totuene but soluble in t4rahydrofur.m (THF) cw pyridine. The mobcular wd;lht, number of condensed aromatic rings, the number of nitrogen, oxy@n and sulfur hrterotltoms and the concentration of metals increases in going from the average molecule in the oil fraction to the average molecufe in the preasphaltene &a&ion [I] a Most of the oxygen in the asphaltenc and preasphaltene fractions is phenolic oxygen and most of the nitrogen is basic ring nitrogen. The physical state of coakkived liquids depends significantly on the reIative amounts of each fraction. Anomalies sre observed when coal liqciefaction slurries containing high levels of asphaltenes and preasphaknes are Ekered in the 2OU-320°C temperaturu range [2). The anoma.E& have been attri