Biobased fuel additives from sugar
As part of the “Bio-FAA” project, the Fraunhofer Center for Chemical-Biotechnological Processes CBP investigated and developed a process for the production of fuels and fuel additives from biogenic isobutene on behalf of the German-French company Global Bioenergies.
Isobutene is one of the key molecules of the petrochemical industry and is currently being produced commercially exclusively from fossil sources, mainly petroleum.
Biogenic isobutene used in the project is manufactured by Global Bioenergies in a self-developed process using renewable raw materials (e.g. cereals, sugar, agricultural or forestry waste). For this purpose, a demonstration plant for the fermentative production of biobased isobutene from sugars was set up on Fraunhofer CBP campus in Leuna with the support of CBP, which Global Bioenergies now operates together with Fraunhofer CBP.
Transforming the biobased analogues to fuels and fuel additives is promising and has been explored and turned into reality in the project. Here, the focus was on the heterogeneously catalyzed conversion to isooctane and ethyl tert-butyl ether (ETBE). Established process concepts were adapted to the biogenic raw material source, and the feasibility of the CBP-operated integrated testing and pilot plants was successfully demonstrated. Finally, corresponding sample quantities of biogenic fuel additives were validated against the products available on the market. During the project, the world's first-ever production of fully renewable ETBE took place in February 2017.