Patent ID: 8887557

Claim:
A method for the chromatographic separation of a de-asphalted oil (DAO) extracted from a petroleum vacuum resid boiling above 1000° F., comprising: a) passing a mixture of the de-asphalted oil (DAO) through a preparative high performance liquid chromatographic separation in columns including a polars column to separate polars; a main column to separate saturates from aromatics; and a sulfides column to separate sulfides to separate the DAO into saturates, aromatics, sulfides, and polars and collecting the separated saturates, aromatics, sulfides, and polars fractions; and b. passing said aromatics fraction through a preparative high performance liquid chromatographic [3-(2,4-dinitroanilino-) propyl]-silica gel (DNAP-silica) column at sub-ambient temperature below 0° C. to fractionate the aromatics into different Classes based upon aromatic ring size and collecting separated 1-Ring, 2-Ring, 3-Ring and 4+Ring-4 aromatic fractions.