E-gasoline or E-benzin is a synthetic fuel created by Audi for use in automobiles. Audi is developing the fuel together with Global Bioenergies S.A. E-gasoline is essentially a liquid isooctane fuel and it is considered to be a carbon-neutral fuel. The fuel is sulfur- and benzene-free.
It is currently produced from biomass in a two-step process. In the first step gaseous isobutene (C<sub>4</sub>H<sub>8</sub>) is produced by Global Bioenergies. Then, in the second step, Fraunhofer Center for Chemical Biotechnological Processes adds additional hydrogen to transform it into isooctane (C<sub>8</sub>H<sub>18</sub>).