Volatile-char interactions during biomass pyrolysis: Reactor design toward product control

This paper proposes a novel reactor featuring controllable adjustment of volatile-char interactions to investigate the pyrolysis of poplar wood and corresponding products. Controllable adjustment of volatile-char interactions enables the selective production of pyrolysis products. The oxygen content in biochar nearly disappears with the reduction of volatile-char interactions and the pore structure of biochar is improved after the interactions being intensified. Moreover, as the interactions reduce, the bio-oil yield increases by 1.23 times, and the outputs of acetic acid and phenols in the bio-oil exhibit decreasing trends, while that of levoglucosan is improved by nearly 4.5 times. Furthermore, the average molecular weight of bio-oil decreases from 786 to 322 g/mol with the continuous intensification of volatile-char interactions. It concludes that the controllable adjustment of volatile-char interactions plays a vital role in regulating the distribution of pyrolysis products and is of great importance to the production of light oil.