Polyaromatic polar content

Further comparisons of data in Table V for the Illinois run 2 and the two Wyodak runs show a reverse trend in monoaromatic, diaromatic and polyaromatic-polar contents in the 200° to 325° C,... 

Figure 4. Polyaromatic-polar vs. nitrogen content, 325°—425° C distillate...

On the other hand, analysis for sulfur and oxygen shows that in the polyaromatic/polar fractions, of an av mol wt of 490, 6.8% sulfur and 2. 6% oxygen represent on the average 1.04 sulfur atoms and nearly 0.7 oxygen atoms per molecule. The material is therefore essentially heterocyclic in character. The nitrogen contents of the fractions were also comparable, suggesting that in the class separation method most of the... 

Since in the simplified procedure only the hydrocarbon fraction from silica is reseparated on alumina, while in the extended procedure all the material remaining after removal of the saturates is rechromatographed on alumina, the contents of polyaromatics from the former is necessarily lower (9.4% ) than from the latter (28.6% ) procedure. The balance of material is represented in the simplified procedure by fraction Polar 1 (see also References 2, 3, and below). 

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