Pyrolysis behavior and kinetic study of phenol as tar model compound in micro fluidized bed reactor

• Pyrolysis characteristics of phenol as tar model compounds were investigated.
• Distribution of gaseous products in micro fluidized bed reactor were determined.
• Apparent activation energies for individual gaseous products were calculated.
• Reaction mechanisms for evolution profiles of gas components were evaluated.

Thermal cracking characteristic of phenol as the model compound of biomass tar was investigated on a micro fluidized bed reactor. Pyrolysis kinetics for individual gaseous component, including hydrogen, methane, carbon monoxide and carbon dioxide were determined based on the iso-conversional and model-fitting approaches. Results indicated that carbon monoxide accounted for the biggest percentage of the total gas yield during pyrolysis of phenol. The evolution profiles of hydrogen energy and carbon monoxide were more affected by reaction temperature compared to methane and carbon dioxide. In the major conversion fraction from 20% to 80%, the apparent activation energies of methane (49.67 kJ/mol) and carbon dioxide (30.87 kJ/mol) were lower than that of hydrogen (145.2 kJ/mol) and carbon monoxide (53.35 kJ/mol). The most probable reaction mechanism for the formation of hydrogen and methane was three-dimension diffusion while chemical reaction and contracting sphere could describe the generation of carbon monoxide and carbon dioxide, respectively.