Continuous Process of Lignin Conversion in a Three –Phase Fluidized Reactor to Produce Aromatic Aldehydes and Organic Acids

The catalytic process of aromatic aldehydes and acid productions from alkaline lignin was operated and evaluated in a three-phase fluidized bed reactor with a palladium catalyst, at the operating conditions of 393K under 5.00 bar of oxygen partial pressure. Lignin obtained as a byproduct from sugarcane bagasse by the DFH (Dedine Fast Hydrolysis, Brazil) process was selected as raw material in order to obtain intermediary oxidation products, such as vanillin, syringaldehyde, p‑hydroxybenzaldehyde and their derivated acids. A heterogeneous model was formulated to describe the transient behavior of the liquid and gas phases in the continuous operations of catalytic wet oxidation of the lignin in the three-phase fluidized bed reactor. Profiles and evolutions of aldehydes and acids concentrations were established at different operating conditions.