Kinetics of Perovskite Catalyzed Biomass Tar Combustion Studied by Thermogravimetry and Differential Thermal Analysis

Biomass tar combustion behavior was investigated with perovskite (CaTiO3, Ca2Fe2O5) as catalysts using heating rates of 5, 10, 15, 20, and 30 °C min−1. The addition of 10 wt % of CaTiO3, Ca2Fe2O5 greatly improved the tar combustion characteristics. For the combustion process, a three stages model, volatilization, low-temperature oxidation (LTO), and high-temperature combustion (HTC), was proposed and applied. The starting temperature of HTC stage was lowered by 30−60 °C, and the combustion residue decreased by nearly 10 wt % resulting from the catalyst’s presence. Different reaction kinetics mechanisms using the classical Arrhenius equation were applied to treat TG data, the results showing the first-order combustion model fitted the data best. Volatilization and HTC stages had large apparent activation energy (E), and a uniform trend of decreasing E was observed in the presence of CaTiO3, Ca2Fe2O5.