There are few options to tackle emissions in the aviation sector, and the adoption of biofuels is one of them. The process of approval for fuels in aviation is intricate. Nevertheless, currently there five types of biofuels approved by the ASTM international D7566 - Standard Specification for Aviation Turbine Fuel Containing Synthesized Hydrocarbons - to be deployed in aviation:
- FT - SPK (Fischer-Tropsch Synthesized Paraffinic Kerosine)
- HEFA (Hydroprocessed Esters and Fatty Acids)
- SIP (Synthesized Iso-Paraffinic)
- FT - SPK/A (Fischer-Tropsch synthesized paraffinic kerosine plus Aromatics)
- ATJ (Alcohol to jet)
Accorind to the standard, those biofuels should be blended to fossil kerosine in a proportion of up to 50%.