Effects of several types of biomass fuels on the yield, nanostructure and reactivity of soot from fast pyrolysis at high temperatures

•Biomass soot samples were generated at fast pyrolysis conditions in a drop tube reactor at 1250 and 1400°C.•The reactivity of soot was determined in 5vol.% O2 and 5vol.% CO2 gasification by thermogravimetric analysis.•The reactivity of soot, generated at 1400°C was higher than that at 1250°C for all biomass types.•Pinewood was less reactive than other soot samples with respect to oxidation and CO2 gasification.•Potassium content played a more important role on the soot reactivity than the particle size and nanostructure.