Characterization of bio-crude components derived from pyrolysis of soft wood and its esterified product by ultrahigh resolution mass spectrometry and spectroscopic techniques

In this work, a detailed analysis of a bio-oil obtained by pyrolysis of softwoods and its esterified product is described. Information of the type of chemical function groups were obtained by C-13 and H-1 nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy (FT-IR) and compositional analysis was obtained by Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS). The results obtained indicate that aliphatic hydrogen and carbon atoms are found in higher abundance, compared with aromatic hydrogen-carbon frameworks. Furthermore, a decrease in oxygen functional groups was observed after esterification. According to the FTICR MS results, the samples contain highly oxygenated species corresponding to compound classes O-x, NOx and BOx, with a high predominance of O-x species. After esterification, the compositions shifted towards lower oxygen-content, lower number of rings and double bonds, and longer alkyl chains as a consequence of the water removal via the condensation reaction.