Molecular Dynamics Study of Propane Hydrate Dissociation: Nonequilibrium Analysis in Externally Applied Electric Fields

摘要

Nonequilibrium molecular dynamics simulations have been performed to investigate both thermal- and electric field-driven breakup of planar propane hydrate interfaces with liquid water at 250-300 K and in the 0-0.7 V nm(-1) field intensity range. The melting temperatures of each interface were estimated, and dissociation rates were observed to be strongly dependent on temperature, with higher dissociation rates at larger overtemperatures vis-a-vis melting. It was found that externally applied electric fields below a certain intensity threshold do not lead to any marked structural distortion or dissociation effect on pre-existing bulk clathrates. However, field strengths higher than 0.7 V nm(-1) led to statistically significant differences in the observed initial dissociation temperature and rates. The activation energy in constant electric field was calculated based on the Arrhenius equation. The parameters of this equation, in terms of both kinetic and thermodynamics components (A and E-a), change significantly, accelerating the dissociation process.