Due to the presence of colloids and asphaltenes
, the viscosity of petroleum and its derivatives is usually high.
The solvent extract was separated into saturate, aromatic and resin fractions with a silica gel:alumina (3:1) column after the precipitation of asphaltenes
. The saturate fractions were analyzed using an Agilent 6890 gas chromatograph equipped with a fused silica column (30 m * 0.32 mm ID * 0.2 [micro]m film).
A Study of the Structure of Petroleum Asphaltenes
and Related Substances by Infrared Spectroscopy.
In 1982, Hyne, Clark and their collaborators demonstrated that metal complexes can accelerate the thermal degradation of large organic molecules such as asphaltenes
in the presence of water, a reaction they termed aquathermolysis [3-5].
On average, BP tarballs contained between 10-18% of a semi-solid mixture of high-molecular weight hydrocarbons, resins, and asphaltenes
. Such mixtures cannot be analyzed using conventional GC methods.
Another critical aspect is the choice of an "aging parameter." Since oxidation alters the bitumen composition, aging evaluation may be approached starting from the well-known fractionation proposed by Corbett  in saturates, naphthene aromatics, polar aromatics, and asphaltenes
, in the order of their increasing molecular polarity.
Bitumen is composed of saturates, aromatics, resins, and asphaltenes
. For ageing, acceleration movement of bitumen molecules causes the evaporation of internal light-weight components so that a series of physical and chemical changes occurred and the content of asphaltenes
According to Corbetts's method , these chemical elements combine to form the four main components or fractions of asphalt cement: asphaltenes
, saturates, naphthalene aromatics, and polar aromatics (or resins), each of which provides different characteristics to asphalt.
Paraffin and asphaltenes
, known to be a problem in the system, were minimized.