Solubility of Gases Near Hydrate Formation Conditions

6 Solubility of Gases Near Hydrate Formation Conditions 

There are only few data sets of aqueous solubility for systems with hydrates (1) methane and ethane solubility in water as a function of temperature ramping rate (Song et al. 1997), (2) carbon dioxide solubility in water by Yamane and Aya (1995), (3) methane in water and in seawater (Besnard et al., 1997), (4) methane in water in Lw-H region [see Servio and Englezos (2002) and Chou and Burruss, Personal Communication, December 18,2006, Chapter 6], As a standard for comparison, Handa s (1990) calculations for aqueous methane solubility are reported in Table 4.3. 

While Table 4.3 shows solubility both above and below the hydrate point, at the three-phase hydrate condition Handa s predictions show a sharp maximum in solubility with pressure at constant temperature. In Holder s laboratory, Toplak (1989) measured the solubility of gas in liquid water around the hydrate point, both in water that had formed hydrates and in water with no residual structure his results show no dramatic change in pure component solubility at the three-phase (Lw-H-V) condition. Kobayashi and coworkers (Besnard et al., 1997) measured a significant solubility increase at the hydrate point beyond that calculated using Henry s law. However, comprehensive solubility measurements around the hydrate point await further experiments. 

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