Comparison of hydrogenolysis with thioacidolysis for lignin structural analysis

Abstract

Abstract Mild hydrogenolysis has been compared with thioacidolysis as a method for degrading lignins in situ and in isolated form before analysis by gas chromatography/mass spectrometry and quantitative 31 P nuclear magnetic resonance (NMR) spectroscopy. Both degradation methods gave similar levels of β-aryl ether-linked phenylpropane units that were released as monomers. Degradation by hydrogenolysis generally gave lower levels of total phenylpropane units when analyzed by 31 P NMR, especially in the case of lignins with high levels of condensed units. Overall, these results indicate that mild hydrogenolysis could offer an alternative to thioacidolysis for probing lignin structure.