Fig. 1. Typical titration curves of wood bio-oil produced at 500 C. (a) The titrant is
sodium hydroxide and the solvent is a mixture of 50% toluene, 49.5% isopropanol
and 0.5% water. (b) The titrant is TMAH and the solvent is acetone and tert-butanol
with a volume ratio of 1:9.