TG-FTIR Analysis of Pyrolytic Lignin Extracted from Different Kinds of Bio-Oil

As one of the most important components in bio-oil, pyrolytic lignin has a close relationship with the property of bio-oil, which also be considered as a potential source to produce value-added chemicals due to its aromatic structure. To improve the stability and increase the economic value of bio-oil, three types of pyrolytic lignin extracted from different kind of bio-oils were studied in this paper. Thermo-gravimetry coupled with FTIR analysis was applied to determine the thermal decomposition behavior and real-time analysis of gases generated during the pyrolysis process. The results were compared with that of the raw alkali lignin, which indicated that PL is more sensitive to temperature and has a lower decomposition temperature range. The analysis on gases generation indicated pyrolytic lignin had less ether bonds, methoxy and hydroxyl groups than alkali lignin. The TG analysis indicated that pyrolytic lignin extracted from larch bio-oil had the lowest residue yields among the three types of PL. The yields of gases from PLs pyrolysis were lower than alkali lignin.