Molecular insight into pyrolysis processes via reactive force field molecular dynamics: A state-of-the-art review

Abstract

Molecular simulations based on reactive force-fields (ReaxFF) have been applied as a powerful tool for exploring the pyrolysis process of complex carbonaceous materials. It can describe the breakage and formation of bonds during the chemical reaction processes based on Bond-Order so as to explore the complex reaction mechanisms from microscale, which can offset experimental flaws. In this review, we attempt to provide an overview of the state-of-the-art advances in the pyrolysis process of coal, biomass, polymer and fuel at molecular level. First the major constituent elements, development, force field optimization, diverse application of ReaxFF MD is introduced. Then, the kinetics models, pyrolysis mechanisms and products reaction pathways of coal, biomass, polymer and fuel are discussed. In addition, the train and optimization of force field and post-processing of simulation are discussed, which can improve reaction analysis capability and provide new ideas to extract information. We conclude the pyrolysis application using ReaxFF MD from microscopic level with an eye toward the future challenges and developments in those fields.