Yang et al. (2004) reported that cellulose and hemicellulose
decompose at 220–340 C, whereas lignin decomposition occurs
>340 C. It is thought that each type of biomass has the potential
to produce maximum bio-oil yield at a certain temperature. Further
increases in temperature facilitate conversion of the bio-oil
into gas products. The decline in bio-oil yield and abrupt increase
in syngas yield at 700 C may have been due to secondary decomposition
of biochar and pyrolysis vapors at the high pyrolysis temperature
(Ertas and Alma, 2010; Imam and Capareda, 2012).