COMPOSITION OF HEAVY PETROLEUMS .3. AN IMPROVED BOILING-POINT MOLECULAR-WEIGHT RELATION

The first two papers in this series (Energy Fuels 1987, 1, 2; 1988, 2, 597) introduced the concept of extended atmospheric equivalent boiling point (AEBP) to molecular distillates of petroleum residues. In this paper we describe three correlations between AEBP and M(n) (number average molecular weight) by means of a third variable, where the latter may be (a) specific gravity, (b) H/C ratio, or (c) refractive index. These correlations, we believe, are better than earlier ones between mid-boiling point, molecular weight (MW), and specific gravity. By applying them to atmospheric residue fractions obtained by molecular distillation we have doubled the range from a previous upper limit of less than 450 to 950 MW, or from about 1000-degrees to over 1300-degrees-F AEBP.