distillates, petroleum, heavy, solvent extract, vacuum is a complex combination of hydrocarbons produced by the vacuum distillation of extracts from a solvent extraction process. It consists predominantly of aromatic hydrocarbons having carbon numbers predominantly in the range of C24 through C30 and boiling in the range of approximately 400.degree.C to 445.degree.C (752.degree.F to 833.degree.F). This stream is likely to contain 5 wt. % or more of 4- to 6-membered condensed ring aromatic hydrocarbons.
