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Updated: Jun 5, 2026
08:46
Methane Hydrate Crystallization on Sessile Water Droplets
Published on: May 26, 2021
Bubble nucleation as a non-equilibrium phase transition in CO2/CH4hydrates
Junde Huang1, Yongxiao Qu1, Gaoyang Luo1
1Department of Physics, Research Institute for Biomimetics and Soft Matter, Jiujiang Research Institute and Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, People's Republic of China.
Summary
This study reveals how carbon dioxide (CO2) and methane (CH4) hydrates dissociate and form bubbles. CO2 aids initial bubble formation, while CH4 drives bubble growth, creating a unique core-shell structure.
Area of Science:
- Condensed matter physics
- Chemical engineering
- Materials science
Background:
- Gas hydrate dissociation is crucial for methane recovery and CO2 sequestration.
- The microscopic mechanisms of hydrate melting and gas-phase formation in mixed systems are not well understood.
Purpose of the Study:
- To investigate the thermodynamic behavior and bubble nucleation during CO2/CH4 hydrate thermal dissociation using molecular dynamics.
- To elucidate the competitive roles of CH4 and CO2 in bubble formation and growth.
Main Methods:
- Molecular dynamics simulations were used to model the thermal dissociation of heterogeneous CO2/CH4 hydrates.
- A long short-term memory (LSTM) model was employed to predict bubble growth dynamics.
Main Results:
- Hydrate melting is a cooperative phase transition dependent on the hydrogen-bond network, with melting temperature increasing with CH4 fraction.
- Bubble nucleation occurs in three stages: induction, nucleation transition, and stabilization, directly linked to hydrate lattice dissociation.
- CO2 lowers the apparent melting temperature, facilitating nucleation, while CH4 dominates bubble growth due to higher supersaturation.
- A CO2-enriched interfacial layer forms, enhancing CH4 aggregation and leading to a CH4-core/CO2-shell bubble structure.
Conclusions:
- The study provides a detailed microscopic understanding of dissociation and bubble nucleation in multicomponent gas hydrates.
- Findings offer insights into non-equilibrium phase transitions and interfacial phenomena relevant to energy and environmental applications.
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