[1] It contains significant amounts of isopentane (methyl butane) CH(CH3)2(C2H5), which is rare in the petroleum product.
[4] Its properties are standardized by GPA Midstream (formerly Gas Processors Association).
It is then transferred to a blender, which will add this E98 to conventional gasoline to make common 87 octane fuels (E10).
However, when mixed with higher concentrations of ethanol (RON roughly equal to 113[6]) 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 produced by extraction processes[7] in the field, as opposed to refinery cracking of conventional gasoline.