Bio-oil can be stabilized and converted to a conventional hydrocarbon fuel by removing the oxygen through hydrotreating. Hydrotreating to remove nitrogen and sulfur from hydrocarbons is a common and well established refinery process.

There are many concurrent reactions. With the condition of applying high H2 pressure, than the dominant reaction will be saturation of double bonds and cleavage of oxygen, leaving behind a wax like product. When there is anything to promote cracking than the followings can happen: no catalyst: cleavage in beta position and giving birth mainly to ethylene and shorter chain alkene-like products that are hydrogenated to saturated one (including the ethylene), if there is an acidic catalytic active center, accessible to the hydrocarbon chain, than the dominant short chain break away products are mainly propylene. acidic sites can promote some isomerization and chain closure.  There is plenty of literature in this area

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