3.2.3. Effect of heating rate on bio-oil properties
The effects of heating rate on the basic properties of bio-oil are
shown in Table 2. The pH value and viscosity of the bio-oil change
little, whereas water content slightly decreases with increasing
heating rate. The carbon content decreases, whereas oxygen content
increases with increasing heating rate. Nitrogen, hydrogen,
and sulfur contents barely change.
The water content of bio-oil reaches 62.8–69.5%. This water
partly comes from a small amount of bound water in moso bamboo
and partly from the thermochemical reactions of cellulose, hemicellulose,
and lignin. The water content of the bio-oil obtained
from slow pyrolysis is higher than that of the bio-oil obtained from
fast pyrolysis (typical fast pyrolysis conditions: 500 C, residence
time