Characterization and Analysis of Char Produced by Biomass Fast Pyrolysis

Pore structure properties of chars obtained by fast pyrolysis of different biomass species under different temperatures are extensively investigated. The carbon content and the calorific value of all pyrolysis chars produced are high. Pore adsorption characteristics of the chars are assigned to be a type III adsorption isotherm curve. Almost all pore diameters are larger than 2 nm, which are allocated to be macroporous and mesoporous. It is found that the pore adsorption capacity of pine pyrolysis char increases with the elevated temperature at the beginning step of pyrolysis, declining after the temperature is over 550°C. Its maximum surface area is up to 725.6 m²/g.