Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : July 18, 2024
During the reaction processes of pyrolysis and gasification, biomass releases small molecular compounds and simultaneously produces thermally stable char. Understanding the characteristics of compounds with a wide range of molecular weights is important to achieve a high degree of control over the products of pyrolysis and gasification. However, compared to tar and gas among pyrolysis products, char is difficult to analyze experimentally, and its molecular structure and formation mechanism have not been clarified in many aspects. In this study, the mechanism of char formation in the initial pyrolysis of lignin was investigated using ReaxFF-MD simulations, which can analyze the pyrolysis behavior of organic materials at the molecular level. Isothermal simulations of the initial pyrolysis of lignin were performed for 500 ps at 11 temperatures between 873 and 2873 K. The simulation results showed that the initial pyrolysis of lignin was not affected by the thermal decomposition of lignin. Analysis of the molecular structure of char in this computational model suggests that it develops a polycyclic structure through ring-opening and ring contraction.
