Study on pyrolysis mechanism of lignin dimer modelwith β-O-4 linkage

Density Functional Theory(DFT) was employed to study the pyrolysis mechanism of lignin dimer model (guaiacylglycerol-β-guaiacyl ether). The results show that the Bond Dissociation Energy(BDE) of the Cβ-O bond homolytic cleavage and the energy barriers of two concerted decomposition reactions are much lower than the BDE of the Cα-Cβ bond homolytic cleavage in the initial decomposition of the dimer compound. The further investigations were then performed to analyze the subsequent pathways and products of the Cβ-O homolysis mechanism and two concerted decomposition mechanisms. The Cβ-O homolysis mechanism is the most favorable pyrolytic mechanism of the dimer compound, and the most energetically favorable pyrolytic products are guaiacol and 3-methoxy-4-hydroxy styrene. ©, 2015, Science Press. All right reserved.