A molecular dynamics simulation study on solubility behaviors of polycyclic aromatic hydrocarbons in supercritical water/hydrogen environment

• Published in: International journal of hydrogen energy 2021-01, Vol.46 (3), p.2899-2904
• Main Authors: Ding, Weijing, Shi, Jinwen, Wei, Wenwen, Cao, Changqing, Jin, Hui
• Format: Article
• Language: English
• Subjects: Hydrogen; Molecular dynamics; Polycyclic aromatic hydrocarbons; Solubility; Supercritical water
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2020.05.084

Violates containing polycyclic aromatic hydrocarbons (PAHs) were precipitated in the process of fast pyrolysis and gasification of coal and organic substances. PAHs are one of bottlenecks of entire coal gasification for hydrogen production. In current work, the solubility of PAH oil droplets in supercritical water/hydrogen circumstances were investigated based on molecular dynamics simulation, which was beneficial for understanding the solubility behaviors of PAHs in supercritical water/hydrogen environment. The results showed that heavy PAHs were rather stable in the water phase. Supercritical water along with hydrogen promoted the miscibility of PAHs compared with that of pure supercritical water. Furthermore, high density and high temperature facilitated the rapid solvation of PAHs in supercritical water/hydrogen environment. This paper is expected to provide a theoretical support for the development of complete coal gasification technology for hydrogen production. Schematic illustration of an oil droplet in supercritical solvent environment. [Display omitted] •Solubility of PAHs in SCW/H2 was studied by MD simulations.•Increasing temperature and density enhanced solubility behaviors.•It was observed that hydrogen penetrated water shells.•Hydrogen promoted the dispersion of PAH oil droplets.