Molecular Dynamic Simulation of Methane Hydrate Decomposition with Polyvinyl Alcohol at Different Concentrations

作者：Chen Yujuan^*; Wang Yanhong; Fan Shuanshi; Lang Xuemei

来源：Acta Chimica Sinica, 2010, 68(22): 2253-2258.

• polyvinyl alcohol
• methane hydrate
• molecular dynamic simulation
• decomposition

Methane hydrate decomposition was investigated by molecular dynamic simulation adding with polyvinyl alcohol. Three kinds of methane hydrate systems with polyvinyl alcohol concentration of 2.7 wt%, 5.2 wt%, 7.6 wt% respectively were studied. Water moleculars in methane hydrate fluctuate near the equilibrium position when polyvinyl alcohol (PVA) concentration is 2.7 wt%, with diffusion coefficient 1.04 X 10(-11) m(2)/s; while at 5.2 wt% PVA solution, methane hydrate structure was disrupted, most methane escaped from the cages, with diffusion coefficient of water molecular 1.61 X 10(-9) m(2)/s, showing good ability of hydrate decomposition. Hydrogen bond was observed between PVA itself, causing steric hindrance in hydrate formation. A small parts of methane hydrate cages at interface were disrupted, resulting some methane escaped, the diffusion coefficient of water molecular is 3.55 X 10(-10) m(2)/s in 7.6 wt% PVA solution. As for effect on decomposition of methane hydrate, PVA concentration 5.2 wt% is the greatest, while the PVA concentration 2.7 wt% is the least. This work provides great reference value for the experimental investigation into the effect of PVA on the hydrate dissociation.

• 出版日期2010-11-28
• 单位华南理工大学