What is gasoline?

Gasoline is a term with which we are familiar, practically, since we have proof of our existence. Refueling at a service station is a routine practice, but do you know exactly what gasoline is?

From a young age, we hear our parents phrases like “I have to go get gas” or “I have to look for cheap gasoline to refuel.” When we already have a driver’s license, we begin to pay more attention to the price of gasoline and we become familiar with terms such as 95 or 98 gasoline, without knowing in many cases the difference between the two.

Perhaps it is best to start at the beginning. What is gasoline? It consists of a mixture of hydrocarbons obtained by distillation and subsequent chemical treatment of oil. It is mainly used to power internal combustion engines, although it also has other uses, such as heating.

To obtain gasoline, oil is subjected to a fractional distillation process, after which various products are obtained, including gasoline and also diesel.

Gasoline must meet certain environmental conditions and requirements so that it can be used in engines, such as, for example, the octane number, which refers to the resistance of the fuel to detonation.

Without further delay, we are going to explain what gasoline is, what characteristics it has, how it is obtained and what types there are according to their octane rating.

Meaning and characteristics of gasoline

Gasoline is a combination of various liquid, volatile and flammable hydrocarbons, that is, organic compounds formed only by carbon and hydrogen, which is obtained by fractional distillation of oil to which additives are added to improve its properties.

This fuel is used, above all, in internal combustion engines and its most important characteristic is its octane number. A gasoline will be better the greater its number of branched alkanes and, for this, it is subjected to high pressures and with platinum catalysts.

This octane number is a measure for the anti-knock power of a gasoline. If the gasoline ignites before the piston reaches the end of its stroke, detonations occur, which is detrimental to the engine. The way to avoid this problem is through branched hydrocarbons.

On the other hand, to improve the octane number, some additives are usually added. Formerly they contained lead, but it is currently in disuse due to its environmental danger and anti-knock ethers are often used.

obtaining gasoline

Gasoline is obtained from petroleum, which is a mixture of different hydrocarbons, cycloalkanes and aromatic hydrocarbons. As we have said before, crude oil undergoes several fractional distillations from which different products are obtained, depending on the boiling point: asphalt, oil, kerosene, diesel, gasoline…

Over time, due to the growing demand for gasoline, different procedures have been developed to extract oil, such as cracking, which consists of converting hydrocarbons with longer chains, with few applications, into shorter ones such as gasoline. thanks to high temperatures and pressures.

Types of gasoline according to their octane rating

Octane is the temperature and pressure ratio to which gasoline can be subjected when compressed by the cylinder during the combustion process when it explodes.

The higher the octane number, the better the quality of gasoline. Depending on the octane number, different types of gasoline are marketed: gasoline 95 and 98.

95 gasoline: contains little sulfur and is not very harmful to the environment. Its refinement makes it less aggressive for the engine and lengthens its useful life, while keeping it free of impurities.

98 gasoline: in this case it contains less or no sulfur in its composition. It reduces consumption compared to other types of gasoline and its use is more favorable for the engine and for the environment. This gasoline is recommended for high-performance vehicles.

Related terms

There are a number of terms related to gasoline, although they are not the same. Many times, we use the expression “fill gasoline” even if our car is diesel or other fuel.

Diesel

Also called gas oil or gas oil, it is a liquid hydrocarbon that is made up of paraffins.

It is mainly used for diesel engines in the automotive sector and as a fuel to heat buildings and homes. It stands out for having a great calorific power.

biodiesel

It is a fuel similar to diesel, but it is obtained from vegetable oils, animal fats or recycled fats and its combustion is cleaner.

The biggest difference between diesel and biodiesel is that diesel is a non-renewable energy source that is running out, while biodiesel is a renewable energy source.

Liquefied Petroleum Gas or Autogas

LPG (Liquefied Petroleum Gas) or Autogas is characterized by being a gas in its natural state, but it changes to its liquid state when subjected to low temperatures and low pressures.

This characteristic facilitates its handling in the refineries, in its storage, transport and for consumption by the end user.

Compressed natural gas

Compressed Natural Gas (CNG) is an alternative to fuels derived from petroleum, much more expensive and polluting.

It is composed of 80-90% methane and the rest is constituted by additions of carbon dioxide, nitrogen and hydrocarbons.

Hydrogen

It is the cleanest fuel source. It can be used conventionally, in fuel cells or to produce electricity.

However, their collection, storage, transport and refueling require high energy costs.