Characteristics of clathrate hydrate equilibria in mesopores and interpretation of experimental data

The characteristics of clathrate hydrate equilibria in mesoporous media are discussed in terms of a conceptual model, with the aim of resolving current inconsistencies concerning experimental and interpretative methods employed in studies of such systems. This conceptual model is used as the basis for an analysis of experimental results from our own work and that of others. From this review, we conclude the following: (1) the Gibbs-Thomson (or Kelvin) relationship used to model clathrate inhibition in porous media must be modified correctly to reflect the hysteresis between growth and dissociation; (2) step heating provides more-reliable data than continuous heating techniques; (3) if equilibrium dissociation data cover the complete pore size distribution, then, contrary to what has previously been proposed by some researchers, inhibition can be interpreted in terms of the mean pore diameter; and (4) the enthalpy of clathrate dissociation is not a strong function of pore size (crystal size), as has been suggested in other studies.