Nucleation rates of carbon dioxide hydrate

• CO 2 hydrate nucleation rates measured in bulk aqueous phase. • CO 2 hydrates nucleate faster than those formed from methane or a gas mixture. • Higher solubility of CO 2 in the aqueous phase does not significantly affect the nucleation rate. • Lower energy penalty for introducing the CO 2 hydrate-water interface yields fast kinetics. Nucleation rates of carbon dioxide hydrate were extracted via the measurement of induction time distributions in a set of stirred, stainless steel, high-pressure cells. These nucleation rates ranged from (1.71 to 20.6) × 10 -4 s −1 at subcoolings between (1.2 and 4.2) K, higher than those measured under the same conditions for methane or structure II hydrates. Formation probability was well-described by the mononuclear mechanism from Classical Nucleation Theory. Analysis under this framework reveals that the comparatively faster nucleation rates observed for CO 2 hydrates can be attributed to lower nucleation work rather than guest solubility in the liquid aqueous phase.