Petrol

Petrol is a light distillate obtained from oil that contains hydrocarbons with a carbon atom number of C4-C12 and with a typical distillation interval of between 30°C and 200°C, and it is ideal for fuelling internal combustion engines. 
Petrol is obtained by mixing components from different plants, even if they are not all present in the various refineries.

The most frequently used products are:

• Butane (C4), from various refinery plants;
• Virgin Naphtha, straight run from primary distillation;
• Reformed Naphtha, from catalytic reforming;
• Light Catalytic Naphtha (LCN), from catalytic cracking;
• Isomers, from an isomerization process;
• Alkylates, from an alkylation process;
• MTBE or other ether oxygenates (ETBE, TAME);

The specific European norm for unleaded petrol is EN228, which standardises the norms governing unleaded super petrol throughout Europe, while the Italian version is UNI EN 228.

According to the number of the Research Octane Method, unleaded petrol is divided into normal ( > 95 RON) and super (>98 RON).

Environmental petrol norms are defined by the European Union in its Directive 2009/30/CE, while  other norms are defined by the CEN.

Since 1 January 2009,  commercialised petrol no longer contains sulphur.

Petrol can be mixed, in ratios defined by the technichal norms, with some bio-fuels such as ethanol or ETBE.