Molecular Dynamics Simulation on Crystallization Kinetics of Sodium Sulfate in Supercritical Water

doi:10.19596/j.cnki.1001-246x.8012

Abstract

Abstract: Sodium sulfate is a common inorganic salt that causes blockage in supercritical water (SCW) reactors. An investigation of its crystallization kinetics is important for the design of deposition-preventing reactors. Microscopic crystallization process of sodium sulfate in SCW was studied with LAMMPS molecular dynamics simulation. Water molecule was calculated with SPC/E model, and ion-ion and ion-water interactions were calculated with Coulumb and Lennard-Jones combined potential energy functions. It shows that the impact of water on electrostatic shielding effect of ion charges decreases at higher temperatures and lower densities. Increasing temperature and density is advantageous to diffusion of ions, which helps ions to collide and form nuclei. Magnitude of nucleation rate is generally in the order of 10²⁹ cm^-3s^-1 in simulated parameters range of SCW.

Key words: supercritical water, sodium sulfate, nucleation, molecular dynamics simulation

CLC Number:

TQ115

ZHOU Lu, MA Honghe. Molecular Dynamics Simulation on Crystallization Kinetics of Sodium Sulfate in Supercritical Water[J]. CHINESE JOURNAL OF COMPUTATIONAL PHYSICS, 2020, 37(2): 212-220.

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