There are three methods to refine feedstock into biokerosene: hydrogenation, the Fischer-Tropsch process, and nanoemulsion with polarization.

17.4.2.1 Hydrogenation

Hydrogenation is a hydrocracking process in a catalytic reactor whereby 30 kg per tonne hydrogen is added to the crude Jatropha oil in order to condense the oil’s energy content. Also, the oxygen is removed as carbon dioxide or carbon monoxide. This process is called hydrogenation (also known as hydroprocessing, hydrotreating, or hydrocracking). The resulting fuel is functionally the same as petroleum-based jet fuel, with the especially important characteristic of not freezing until —57°C, 21% better than the Jet A-1 specification of —47°C. The refining process is very similar to the hydroprocessing that takes place in petroleum (oil) refineries to produce jet fuel and other products. This process can yield a 70-75% fraction of jet fuel from the feed oil, with the remaining 25-30% converted to naphtha and propane ("liquid petroleum gas”). This hydrogenation process for producing bio jet fuel is
the most commercially advanced, with Honeywell’s UOP Division and Syn — troleum both claiming to have licensable processes. From discussions with UOP and Syntroleum, the cost for refining the bio jet fuel (including capital recoup­ment and the refiner’s profit) is estimated to be $0.40-0.65 per gallon.