The bulk shales were crushed into powder in a rotary mill. The
homogenized powdered samples were extracted using a Soxhlet apparatus
with a mixture of dichloromethane-methanol (9:1 v/v) for 72 h. Then,
the extracts were fractionated using two-phase silica gel column liquid
chromatography. Total hydrocarbons were separated from polar compounds
by eluting the extractable organic matter (EOM) with n-hexane/dichloromethane (4:1 v/v). Then, the total hydrocarbons were
separated into aliphatic hydrocarbons, which were collected by eluting
with n-hexane, and aromatic hydrocarbons, which were
collected by eluting with n-hexane/dichloromethane
(4:1 v/v).
homogenized powdered samples were extracted using a Soxhlet apparatus
with a mixture of dichloromethane-methanol (9:1 v/v) for 72 h. Then,
the extracts were fractionated using two-phase silica gel column liquid
chromatography. Total hydrocarbons were separated from polar compounds
by eluting the extractable organic matter (EOM) with n-hexane/dichloromethane (4:1 v/v). Then, the total hydrocarbons were
separated into aliphatic hydrocarbons, which were collected by eluting
with n-hexane, and aromatic hydrocarbons, which were
collected by eluting with n-hexane/dichloromethane
(4:1 v/v).
