Fuels, oils and lubricants

diesel fuel, heating oil, gasoline, gas stations and fuel transport

Gasoline

Gasoline is a liquid mixture of hydrocarbons (especially alkanes, cycloalkanes, aromatic hydrocarbons and alkenes with 5 to 12 atoms of carbon per molecule) produced by fraction distillation from crude oil and used as fuel in spark ignition engines.

Octane number

The octane number is one of the basic characteristics of fuel for spark-ignition engines, it expresses fuel resistance against self-ignition (detonation, so called “knocking”) during compression in a spark-ignition engine cylinder. It is a part of fuel marking and is shown on fuel pumps of gasoline pumps.

The fuel octane number expresses the percentage volume of iso-octane in a mixture of iso-octane with n-heptane that is as resistant against self-ignition as tested fuel (pure n-heptane has an octane number zero, pure iso-octane has an octane number 100). However, the octane number can be higher than 100, which shows that a given fuel is even more resistant to self-ignition than pure iso-octane.

Pure gasoline has a very small octane number. That is why additives to increase the octane number are added to it. In the past, primarily lead compounds were used to achieve this (mainly tetraethylene and tetramethylene of lead). Each liter of gasoline contained several grams of toxic lead. That is why these lead additives are banned today. Today organic-metal compounds of manganese, aromatic amines, or halogenides of transient metals are used as anti-detonators.

Material here is based on information provided by Wikipedia