Formation of Hydrates from Single-Phase Aqueous Solutions and Implications for Oceanic Sequestration of CO2

Gas hydrates are crystalline solids formed from mixtures of water and low molecular weight compounds, referred to as hydrate formers, that typically are gases at ambient conditions (1). Generally, hydrates are formed in the laboratory from two-phase systems by contacting a hydrate former or formers in the gas or liquid phase with liquid water and increasing the pressure until crystalline hydrate forms. However, the formation of hydrate from a single-phase aqueous system using only the hydrate former dissolved in the aqueous phase has been demonstrated in prior work at the National Energy Technology Laboratory (NETL) (2) and more recently by others (3).