The gasoline with lead is withdrawn this year from the market

2001/03/13 Carton Virto, Eider - Elhuyar Zientzia

• Garraioak
• Energia

Poison to increase quality

In the motor of most vehicles, the air and fuel are introduced into the cylinder and compressed so that a spark explodes and reaches the power that moves the vehicle. The small hydrocarbons explode quickly and give little power to the car. The octane, on the other hand, support quite well the compression and give the adequate power to the engine, but in refineries do not make pure octane, among other things because it is expensive. Therefore, the fuel has octane and heptane, and a number is added to the name of the proportion between the two. In the fuels of 95 octane 95% of the hydrocarbon is octane and 5% heptane, while in those of 98 octane 98% is octane and only 2% is heptane.

Super gasoline is 97 octane and its substitute will also be of the same octane, but without lead. The octane of gasoline indicates in some way the quality of the gasoline, since the highest octane supposes a greater power.

To allow the controlled explosion of fuel from the 1930s and increase the number of octane, additives containing lead or manganese were introduced to gasoline. Over time, the level of compression of the fuel used by the engines increased and other compounds such as Tetraetil lead became usual additives.

In the 1930s there was no technology to increase octane and today, although there is technology, the cheapest method to increase octane is still the addition of additives. But since 1975, as a result of environmental awareness, the amount of lead in fuels and the manufacture of cars that did not need lead has been reduced. The catalysts that need these cars are found in the components of the engine structure.

Term of two years

The European Union has launched campaigns for the total elimination of lead and has been working for several years to withdraw the lead gas market. However, super gasoline is still used by many cars and sudden change is impossible. To facilitate the transition, oil companies have launched a special supplement so that users of super gasoline can mix with lead-free gasoline and use it as fuel. Additives are organic salts of sodium, potassium, phosphorus and manganese. In this way, a period of two years is opened to renew the car park and completely eliminate those who need super gasoline.