Disclosed are methods and systems for removing a highly reactive polymer precursor such as carbonyls from a liquid hydrocarbon stream. Embodiments may disclose a method for removal of carbonyls from a liquid hydrocarbon stream comprising the steps of providing a liquid hydrocarbon stream containing carbonyls, providing a liquid bisulfite stream comprising an alkali metal bisulfite, and contacting the liquid hydrocarbon stream and the liquid bisulfite stream in a mass transfer device wherein at least a portion of the carbonyl reacts with the alkali metal bisulfite to form a solid adduct that is soluble in the bisulfite solution.

Method to produce biofuel using a lignin-rich feedstock, said method comprise; providing a lignin-rich feedstock, wherein said lignin-rich feedstock comprises more than 60 wt % of lignin-based compounds obtained from delignification of biomass, where said lignin-based compounds are selected from the group consisting of: lignin-derived monomers, lignin-derived dimers, lignin-derived oligomers and combinations thereof; performing a hydrodeoxygenation reaction on said lignin-rich feedstock, wherein the hydrodeoxygenation reaction is carried out in a hydrogen-rich source at a temperature ranging from 300 C. to 400 C. under a H2 pressure ranging from 15 to 75 bar, more preferably 35 bar, in the presence of a catalyst adapted for HDO reactions, for a period of time sufficient to result in an upgraded oil having a total acid number (TAN) of about 10-35 mg KOH/g and viscosity of 4-30 cP.

Method to produce biofuel using a lignin-rich feedstock, said method comprise; providing a lignin-rich feedstock, wherein said lignin-rich feedstock comprises more than 60 wt % of lignin-based compounds obtained from delignification of biomass, where said lignin-based compounds are selected from the group consisting of: lignin-derived monomers, lignin-derived dimers, lignin-derived oligomers and combinations thereof; performing a hydrodeoxygenation reaction on said lignin-rich feedstock, wherein the hydrodeoxygenation reaction is carried out in a hydrogen-rich source at a temperature ranging from 300 C. to 400 C. under a H2 pressure ranging from 15 to 75 bar, more preferably 35 bar, in the presence of a catalyst adapted for HDO reactions, for a period of time sufficient to result in an upgraded oil having a total acid number (TAN) of about 10-35 mg KOH/g and viscosity of 4-30 cP.