Experimental and Modeling Investigation on the Effect of Intrinsic and Extrinsic Oxygen on Biomass Tar Decomposition

The heteroatoms, such as oxygen, have great influence on tar decomposition reactivity. To investigate the effect of oxygen on biomass tar decomposition, thermal decomposition of three typical oxygenated tar compounds and toluene were conducted under inert and oxidative atmospheres in a flow tube reactor. The key roles of intrinsic oxygen of tar and extrinsic oxygen at controlled atmospheres were taken into consideration. Results show that all three tar compounds were easy to decompose at moderate temperatures accompanied by the polymerization reaction. 2-Methoxyphenol produced less naphthalene compared to anisole under an inert atmosphere. Intrinsic oxygen enhanced the reactivity of tar as well as inhibited the polymerization process. Moderate extrinsic oxygen addition could eliminate tar without sacrifice of combustible gases, such as H-2 and CO. The reaction mechanism generator (RMG) method was used to build a complete detailed kinetic model to simulate biomass tar homogeneous conversion. The new detailed kinetic model could predict the conversion of model tar compounds as well as the real tar mixture.