Investigation of physicochemical properties of biooils produced from yellow poplar wood (Liriodendron tulipifera) at various temperatures and residence times

Fast pyrolysis of yellow poplar wood (Liriodendron tulipifera) was performed under different temperature ranges and residence times in a fluidized bed reactor to maximize the yield of biooil. In this study, the pyrolysis temperature ranged from 400 °C to 550 °C, and the residence time of pyrolysis products was controlled between 1.2 and 7.7 s by inert nitrogen gas flow. The results revealed that the distribution of thermal degradation products (biooil, biochar, and gas) from the woody biomass was heavily influenced by pyrolysis temperature, as well as residence time. The highest yield of biooil was approximately 68.5 wt% (wet basis), with pyrolysis conditions of 500 °C and 1.9 s of residence time. Water content of the biooils produced at different temperatures was 25–30 wt%, and their higher heating values were estimated to be between 15 MJ/kg and 17 MJ/kg. Using GC/MS analysis, 30 chemical components were identified from the biooil, which were classified into 5 main groups: organic acids, aldehydes, ketones, alcohols, and phenols. In addition, biochar was produced as a co-product of fast pyrolysis of woody biomass, approximately 10 wt%, at temperatures between 450 °C and 550 °C. The physicochemical features of the biochar, including elemental analysis, higher heating values, and morphological properties by SEM, were also determined.