ETBE is an oxygenate used as a gasoline blend stock to add octane.

ETBE is manufactured by combining isobutylene with ethanol (often bio-ethanol to get the biofuel credits available in many countries) by heating them together over a catalyst. A number of ETBE process units have been converted from MTBE process units, especially in Europe, as the process is similar (MTBE is based on combining isobutylene with methanol rather than ethanol), but the methanol does not receive biofuel credits.