HCOTEG12260 - Technical Background on Oils: Light and heavy oils

Mineral oil (hydrocarbon oil as defined in the Hydrocarbon Oil Duties Act 1979) is divided into ‘light’ oil and ‘heavy’ oil according to its distillation characteristics.

Light oil includes, motor spirit, aviation spirit and industrial solvents such as toluene, xylene, etc. Heavy oil includes gas oil, kerosene, aviation turbine fuel (AVTUR) and fuel oil.

Descriptions of Mineral (Hydrocarbon) oils

Light Oil

  • Benzole and benzene
  • Cumene
  • Ethylbenzene
  • Motor and aviation Spirit
  • Petroleum ether
  • Rosin spirit
  • Solvent or heavy naphtha
  • Styrene
  • Tetralin and decalin
  • Toluole and toluene
  • Turpentine, dipentene and pinene
  • White spirit and special solvents (e.g. special boiling point spirits )
  • Xylole and xylene ( including ortho-para and meta-xylene)

Heavy Oil

  • Anthracene oil
  • Burning oil (kerosene)
  • Coal tar
  • Creosote oil
  • Diesel oil
  • Fluxing oil
  • Fuel oil
  • Gas oil
  • Lubricating oil
  • Medicinal paraffin
  • Switch gear and transformer oil
  • Technical white oil

Oil which may be either light or heavy

  • Crude oil (crudes from the Middle East are normally light oil by virtue of their flash point)
  • Jet engine fuel. The description known as “wide cut gasoline” (or AVTAG (JET B) and AVGAS are light oils. The types usually known as AVTUR (JET A1) and AVCAT (JP5) are heavy oils