Naphtha, any of various volatile, light flammable liquid containing a mixture of hydrocarbon molecules typically with between 5 and 10 carbon atoms. It mainly consists of straight chain alkanes (paraffins) but it may also contain cyclohexane (naphthene) and aromatics.. Naphtha was the name originally applied to the more volatile kinds of petroleum issuing from the ground in the Baku district of Azerbaijan and Iran.
Naphtha is produced primarily from the distillation of crude oil and is the intermediate product between the light gases and the heavier kerosene. It can also be a component of natural gas condensates, the liquid hydrocarbons contained in natural gas.
There are a number of different classes of naphtha and similar naphtha types may be called by different names. Light naphtha will normally have a higher content of straight chain paraffins and is sometimes referred to as paraffinic naphtha or straight run gasoline. Heavy naphtha usually contains more naphthalene and aromatics and may be called N&A naphtha.
In the petrochemical industry, naphtha is an important feedstock for steam crackers in the manufacture of olefins (ethylene, propylene, butadiene) and aromatics (benzene, toluene, xylene). Paraffinic naphtha are preferred for steam crackers but heavier naphtha can also be used.
Light naphtha can also be used in industrial solvents and cleaning fluids. Applications include varnishes and paints, shoe polish, lighter fluid and fuel for portable stoves and lanterns.
Naphtha is also used to make high octane gasoline using a catalytic reforming process. This process converts heavy, low octane naphtha into high octane products.
Coal-tar naphtha is a volatile commercial product obtained by the distillation of coal tar. Shale naphtha is obtained by the distillation of oil produced from bituminous shale by destructive distillation. Petroleum naphtha is a name used primarily in the United States for petroleum distillate containing principally aliphatic hydrocarbons and boiling higher than gasoline and lower than kerosene.