Effects of metal oxide catalysts on polycyclic aromatic hydrocarbons emissions from large scale biomass pyrolysis

Biomass, as a renewable resource, offers a potential alternative to fossil fuels. Catalytic pyrolysis, a process that converts biomass into bio-oil, is a promising method for sustainable energy production. This study aimed to quantify the concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) in bio-oil produced from metal oxide catalytic pyrolysis of sugarcane bagasse. Using a large-scale auger reactor, bagasse was pyrolyzed at temperatures ranging from 400 to 600 °C with various amounts of vanadium pentoxide (V₂O₅) catalyst (0-30% w/w). The resulting bio-oil was analyzed using gas chromatography/mass spectrometry (GC/MS) to identify and quantify PAHs. Significant levels of PAHs (2206-6498 mg/L) were detected in the bio-oil. Low molecular weight PAHs, such as naphthalene, acenaphthylene, acenaphthene, fluorene, and phenanthrene, were predominant in all samples. The minimum total PAHs concentration (2206 mg/L) was observed at 400 °C with a 20% V₂O₅ catalyst loading. These findings suggest that metal oxide catalytic pyrolysis of bagasse, particularly with V₂O₅, can effectively control and reduce the formation of PAHs. Further research is needed to optimize the process and minimize PAHs production to commercialize bio-oil as a sustainable fuel.