Both hydrodeoxygenation (HDO) and hydrodecarboxylation
(HDC) are simultaneous hydrotreatment processes that occur
during the upgrading of petroleum feedstock, but the scope have
recently be extended to include the upgrading of biomass-based
feedstock like the vegetable oils. The HDO proceeds by the removal
of oxygen from oxygenated compounds (i.e. oxygen containing
compounds) in the feed following the incorporation of hydrogen
and an appropriate catalyst. With vegetable oils, the long chain
glyceride esters contain carbonyl oxygens that could be removed