Pentane-insoluble matter from conventional and heavy crudes: Relationships between thermal characteristics and molecular parameters

Nearly 50% of bitumen derived from Athabasca oilsands is pitch. The pentane-insoluble fraction is the major coke producer during thermal cracking. Here, we evaluate the thermal behavior of pentane insolubles from various oil sources by correlating thermogravimetric data with structural parameters. The effect of any entrained mineral solids on the thermal properties results was also investigated. Coke yields depended significantly on aromaticity, H/C atomic ratios, molecular weight, chain length, and equivalent molecular diameter. With the exception of highly aliphatic Daqing conventional oil, coke yields correlated well with the calculated structural parameters. Asphaltene from bitumen was about average in its coke-forming propensity. Mineral solids had practically no effect on thermal behavior.