Structural evolution of rubber-wood char under different pyrolysis conditions

Abstract

In order to explore the effect of different pyrolysis conditio ns on the structural characteristics of rubber wood biomass pyrolysis, rubber wood char was prepared under fast pyrolysis and slow pyrolysis conditions. The char was analyzed by BET, SEM, FT-IR and Raman spectroscopy to explore the effects of different pyrolysis conditions on pore characteristics, surface structure and chemical structure. The results showed that the nitrogen isothermal adsorption/desorption curves of slow pyrolysis at 900°C are obviously different, and the char structure has a certain amount of mesopores and macropores. With the pyrolysis temperature increased, the alkane side chain of rubber wood char broke, and formeda large number of active sites, which promoted the condensation of small aromatic rings into large aromatic ring structures, and deepened the aromatization of char structures. The rapid pyrolysis method causes the content of the small aromatic ring structure to be greater than that of the large aromatic ring structure at low temperature. The slow pyrolysis method causes the increase of the large aromatic ring structure to be greater than that of the small aromatic ring at a lower temperature contrarily.