ABSTRACT
Petroleum fractions are characterized in different ways depending upon the products that are manufactured. This chapter illustrates some of the more common properties of petroleum cuts and their correlations. When a petroleum fraction is vaporized in the absence of air, the nonvolatile compounds leave behind a carbon residue which is reported in weight percentage. The viscosity of petroleum fractions at atmospheric pressure and temperatures of 100°F (37.8 °C) and 210°F (98.9 °C) is given by Pederson’s relations. The refractive index n of petroleum fractions at 68°F (20 °C) correlate to its mean average boiling point and specific gravity. The freezing point of petroleum fractions is estimated from the mean average boiling point, specific gravity SG, and Watson factor. The cetane index is equal to the percentage of cetane in a blend of cetane and alpha methyl naphthalene having the same ignition quality as a sample of the petroleum fraction.
