KINETICS OF FORMATION OF CO2 HYDRATE

This study proposes a mechanism of the formation of CO2 hydrate at the interface between liquid CO2 and water. A partial differential equation taking into account the diffusion and reaction in the CO2 liquid phase is derived. Computational simulations were conducted, and the model interprets well the many observations on the CO2 hydrate formation in previous papers. Some conclusions were obtained in relation to ocean CO2 disposal from a viewpoint of kinetics on hydrate formation. For example, liquid CO2 disposed at deep ocean will instantly form a very thin film of CO2 hydrate. A concept of long-term sequestration of liquid CO2 by use of thin hydrate film is proposed. The ecological impacts of CO2 will be considerably reduced because of the controlling effect of hydrate film on the dissolution of CO2 into the seawater.