Bioethanol to jet fuel: Current status, challenges, and perspectives

Bioethanol fermentation industry is the first largest fermentation industry in the world. The conversion of bioethanol into liquid transportation fuels, namely gasoline-range, jet-range, and diesel-range hydrocarbons has got more and more attention. However, renewable jet fuel only accounts for less than 0.1% of current global jet fuel demand. Thus, we summarize the current status and challenges of the preparation of aviation kerosene by condensation of bioethanol platform molecules. We first summarize the main technologies for C–C bond coupling of ethanol molecules, namely the Guerbet reaction and ethylene oligomerization. Subsequently, we analyze recent and old developments in the heterogeneous catalysts for the Guerbet reaction and oligomerization. A critical comparison of the two jet fuel production options with each other shows the ethylene-based oligomerization is superior to the Guerbet reaction. The comparison of the bioethanol-to-jet process with other renewable jet production options shows that the current bioethanol upgrading will face a lot of competition from other biomass resources. The challenges and future direction for the bioethanol to jet fuel route are also wrapped up with our opinion on the development of new generations of catalysts and reaction systems.