Microwave heating and collapse of methane hydrate by molecular dynamics simulations

TL;DR

This study uses molecular dynamics simulations to explore how microwave electric fields induce heating and collapse in methane hydrate, revealing density and guest molecule effects on stability.

Contribution

It introduces a detailed molecular dynamics approach to analyze microwave-induced hydrate collapse, considering different densities and guest molecules.

Findings

Collapse occurs at certain densities under microwave irradiation.

Higher density hydrate remains stable and does not collapse.

Guest molecules like CO₂ increase kinetic energy but cause rapid collapse.

Abstract

Microwave heating of methane hydrate is investigated with electrostatic molecular dynamics simulations by the SPC/E water model. The structure I of methane hydrate is constructed. When the methane hydrate with a density of 0.91 $\rm{g/cm}^3$ and temperature of 273 K is exposed to microwave electric fields, it suddenly collapses in liquid after a certain period of irradiation. However, a hydrate with a five percent higher density of 0.95 $\rm{g/cm}^3$ and the same initial temperature shows no collapse as a crystal caused by the microwave. A hydrate with CO$_{2}$ guest molecules has increased kinetic energy but rapidly collapses due to the Lennard-Jones potentials. The methane hydrate with variable density and temperature is presented and exhibits slow heating as a crystal and an unchanging volume.