Hydrocarbons

Like other refined petroleum products obtained from major crude petroleum, diesel contains hydrocarbons. Crude petroleum is composed of three major hydrocarbons: paraffinic (also known as alkanes), naphthenic (also known as cycloalkanes), and aromatic.

The aromatic content of diesel is directly proportional to particulate matter (PM) emissions. Thus, the reduction of aromatic content will also lower PM emissions and soot formation.

In diesel, the hydrocarbons limit is regulated as the maximum limit for polycyclic aromatic hydrocarbons (PAH). These are organic compounds containing two or more aromatic rings.

The polyaromatics value is not regulated in Sudan, but values have been quite low.