Natural gasoline is a natural gas liquid with a vapor pressure intermediate between natural gas condensate (drip gas) and liquefied petroleum gas and has a boiling point within the range of gasoline. The typical gravity of natural gasoline is around 80 API. This hydrocarbon mixture is liquid at ambient pressure and temperature. It is volatile and unstable but can be blended with other hydrocarbons to produce commercial gasoline. The hydrocarbon mixture of natural gasoline are mostly pentanes and heavier (smaller amounts of C6 and C6+), extracted from natural gas, that meets vapor pressure, end-point, and other specifications for natural gasoline set by the Gas Processors Association. Includes isopentane which is a saturated branch-chain hydrocarbon, (C5H12), obtained by fractionation of natural gasoline or isomerization of normal pentane.
Natural gasoline is often used as a denaturant for Fuel Grade Ethanol where it is commonly added volumetrically between 2.0% and 2.5% to make Denatured Fuel Ethanol (DFE) or E98. This process renders the fuel grade ethanol undrinkable. It is then transferred to a blender which will add this E98 to conventional gasoline to make common 87 octane fuels (E10). It can also be added to Ethanol in higher volumetric concentrations to produce High Level Blends of Ethanol such as E85. Natural gasoline has a lower octane content (RON roughly equal to 70) than conventional commercial distilled gasoline, so it cannot normally be used by itself for fuel for modern automobiles. However, when mixed with higher concentrations of ethanol (RON roughly equal to 113) to produce products such as E85, the octane level of the Natural Gasoline and Ethanol mixture is now within the usable range for flex-fuel vehicles.
It may be sourced from production of natural gas wells (see "drip gas") or may be produced by extraction processes in the field, as opposed to refinery cracking of conventional gasoline.