Bimetallic oriented catalytic fast pyrolysis of lignin research based on PY-GC/MS

In this work, catalytic pyrolysis of alkaline lignin over mono- (Fe-Al 2 O 3 -SiO 2 and Mo-Al 2 O 3 -SiO 2 ) and due-metal (Fe-Mo-Al 2 O 3 -SiO 2 ) was studied. All experiments, with or without catalyst, were carried out under different pyrolysis temperatures (300–700 °C) and time (0.1, 0.2, and 0.5 min) using pyrolysis gas chromatography-mass spectrometry (Py-GC/MS). Verification of the MS data with principal component analysis (PCA) revealed that the co-operation effect of bimetallic is obvious. Due-metal catalytic pyrolysis treatments clearly differ from the non-catalytic treatment of lignin, while mono-metal catalyst (both Fe and Mo) had a little effect on product distribution. However, at lower pyrolysis temperature (300 and 400 °C), Fe-Mo-Al 2 O 3 -SiO 2 also has good catalytic activity compared with mono-catalysts. Loading plots showed several pyrolysis products with great differences. Which compounds undergo more thermal decomposition reactions, for example, 2,3-dihydrobenzofuran, 2-methoxy-phenol, and 2,6-dimethoxy-phenol, were influenced by due catalyst greatly. Based on the results, Py-GC/MS combined with PCA proved to be a promising method for testing the behavior of different catalysts.