CO2 hydrate: Formation and dissociation compared to methane hydrate

For CO2 disposal in the form of hydrate it is important to know the decomposition kinetics at moderate pressures and temperatures, similar to those that could be realized in the storage systems. This paper has considered the preservation of CO2 hydrate containing different quantities of CO2, at pressures between 0.1 and 0.3 MPa and temperatures between -3 and 0 degrees C. At the conditions (P, T) of this work, CO2 hydrate does not present any anomalous self-preservation effect, and its dissociation is not affected by subcooling before storage. More than pressure, which is very important for methane hydrate, temperature affects the preservation. The temperature of -3 degrees C assures a good stability at atmospheric pressure, providing that CO2 saturation into the hydrate is not too high CO2 hydrate is generally more stable than CH4 hydrate due to the different activation energy of decomposition.