In-situ catalytic pyrolysis of lignin in a bench-scale fixed bed pyrolyzer

Thermal and in-situ catalytic pyrolysis of lignin were carried out in a bench-scale pyrolyzer. The yield and composition of the bio-oil produced were influenced largely by the type of lignin samples, pyrolysis temperature, and nitrogen carrier gas flow rate. The highest bio-oil yield of 35.95 wt.% was achieved using kraft lignin at 500 °C and a carrier gas flow rate of 600 ml/min. In-situ catalytic pyrolysis resulted in a decrease of the bio-oil yield, but the aromatic product distribution was altered greatly depending on the types of catalysts. In-situ catalytic pyrolysis also showed enhanced selectivity to valuable aromatic hydrocarbons.