Naphtha and gasoline are two important hydrocarbon mixtures which we derive from petroleum. There are two forms of naphtha as light and heavy naphtha. Each fraction contains different hydrocarbon molecules having different numbers of carbon atoms per each molecule. Gasoline, on the other hand, is a fuel that contains hydrocarbons containing around 4 to 12 carbon atoms per each.
What is Naphtha?
Naphtha is a term that we use to name more volatile forms of petroleum. It is a flammable liquid containing a mixture of hydrocarbons. It contains paraffin, naphthenes, and aromatic hydrocarbons. We can produce this mixture using coal tar, shale deposits, tar sands and the destructive distillation of wood. Historically, people called mineral spirits as naphtha, but it is not the same chemical. Most of the times, manufacturers tend to desulfurize and catalytically reform naphtha in order to rearrange the hydrocarbon molecules to get a high octane component of gasoline.
Moreover, the largest source of naphtha in most petroleum refineries is the first unit of operation; crude oil distillation unit. Similarly, the liquid distillate that we get from this unit is “straight-run naphtha”. The initial boiling point if this compound is 35 °C but the final boiling point is 200 °C. Then we further distil the product of this operation unit into two streams; light and heavy naphtha. Light naphtha contains hydrocarbon with 6 or fewer carbon atoms while heavy naphtha contains hydrocarbons with more than 6 carbon atoms.
Due to its high volatility and flammability, we can use naphtha as a solvent, as a fuel and for other industrial purposes. It has many synonyms according to its use; ED-6202, high-flash aromatic naphtha, light aromatic solvent naphtha and petroleum naphtha are some of them.
What is Gasoline?
Gasoline is a petroleum-derived fuel. It is transparent, and we can use it as a fuel in spark-ignited internal combustion engines. This fuel contains the organic compounds obtained from the fractional distillation of petroleum. Moreover, it contains various additives that enhance its properties.
Octane rating is an important measurement we take regarding gasoline. It is the resistance to igniting too early. Higher the octane rating, higher the quality. There are several octane rating grades. At early times, manufacturers used to lead (leaded gasoline) to increase the octane rating, but nowadays it is prohibited due to health concerns.
Gasoline has effects on the environment. Ex: local effects such as smog and global effects such as climate changes. Moreover, this compound can enter the atmosphere in its uncombusted form as well; both as a liquid or as vapour. This occurs via leakage during handling, transportation, delivery, from storage tanks and from spills. This affects the environment because gasoline contains carcinogenic compounds such as benzene.
What is the Difference Between Naphtha and Gasoline?
Naphtha is a term that we use to name more volatile forms of petroleum. There are two forms as light and heavy naphtha. Light naphtha contains hydrocarbon compounds having 6 or fewer carbon atoms while heavy naphtha contains hydrocarbons having 6 or more carbon atoms. Whereas, Gasoline is a petroleum-derived fuel. It contains hydrocarbons with carbon atoms between 4 to 12 per molecule. This is the key difference between naphtha and gasoline. Furthermore, naphtha is useful as a solvent, as a fuel, and for other industrial purposes but, the use of gasoline is as a fuel for spark-ignited internal combustion engines. The below infographic presents the difference between naphtha and gasoline in tabular form.
Summary – Naphtha vs Gasoline
Naphtha and gasoline are petroleum-derived hydrocarbon mixtures. The key difference between naphtha and gasoline is that the term naphtha describes the more volatile forms of petroleum whereas gasoline is a petroleum-derived fuel.
1. Britannica, The Editors of Encyclopaedia. “Naphtha.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 11 Dec. 2007. Available here
2. “Gasoline.” Wikipedia, Wikimedia Foundation, 9 Aug. 2018. Available here