超临界水甲烷制氢的分子动力学研究

In order to explore the kinetic mechanism ol hydrogen (H₂) production in supercritical water, this study uses reactive molecular dynamics method to systematically compare the effects of simulation time and molecular number of methane (CH₄() on the concentration-time evolution of key species and reaction channels, and to quantitatively analyze the multi-parameters influence on the pathways of CH₄, consumption and H₂ generation. Results indicate that CH₄, can be converted into H₂ and CO, together with trace number of carbon-based intermediates insupercritical water. Reaction H₂O H-H-*¦-OH + H₂ dominates the generation of H₂, during which the relative number of -OH radicals and -H atoms significantly influences the output of H₂. Under the conditions investigated in this study, reduction in both temperature and pressure shows limited effect on the dominant reaction pathways during CH₄, consumption but presents a promotion on H₂ net production. Decrease in CHi mass concentration increases first and then decreases H₂ net production, suggesting an optimal concentration of CH₄,, for the thermal chemistry conversion in supercritical water. The research results can provide a reference for improving the efficiency of hydrogen production of volatile components in supercritical water.