Tretbar, MaikMaikTretbarWitzel, ThomsenThomsenWitzelHauffe, AnikaAnikaHauffeJunghans, UlrikeUlrikeJunghansBulc, AlesAlesBulcPufky-Heinrich, DanielaDanielaPufky-Heinrich2022-03-052022-03-052018https://publica.fraunhofer.de/handle/publica/25503910.3390/catal8110514This work evaluates the direct etherification of bio-sourced isobutylene with ethanol forming fully renewable ethyl tert-butyl ether (ETBE). Challenge was the use of the fermentative produced substrate in a solvent-free catalysis using the acidic ion exchanger Amberlyst-15. CO2 impurities have a significant influence on the liquid phase process. The conversion at a ratio that is based on molarities of isobutylene to ethanol of 1:0.9 results in yields up to 97 mol% ETBE. Purities up to 99 wt.% could be achieved by subsequent water extraction in order to ensure qualities for technical application as high performance fuel additive.enethyl tert-butyl ether (ETBE)biofuel additivebio-sourced isobutyleneetherificationAmberlyst-15660610620journal article