16540
J. Phys. Chem. B 2004, 108, 16540-16547
Dissociation Conditions of Methane Hydrate in Mesoporous Silica Gels in Wide Ranges of Pressure and Water Content Eugeny Ya. Aladko,‡ Yury A. Dyadin,†,‡ Vladimir B. Fenelonov,§ Eduard G. Larionov,‡ Maxim S. Mel’gunov,§ Andrej Yu. Manakov,*,‡ Anatoly N. Nesterov,| and Fridrikh V. Zhurko‡ NikolaeV Institute of Inorganic Chemistry SB RAS, 3 Prospekt Akad. LaVrentieVa, NoVosibirsk, 630090, Russian Federation, BoreskoV Institute of Catalysis SB RAS, 5 Prospekt Akad. LaVrentieVa, NoVosibirsk, 630090, Russian Federation, and Institute of Earth Cryosphere SB RAS, 86, Malygina str., Tyumen, 625026, Russian Federation ReceiVed: April 13, 2004; In Final Form: July 30, 2004
The temperature of methane hydrate dissociation in silica mesopores has been monitored within a wide range of pressures from 10 MPa to 1 GPa. Because the determination of pore size appears to be crucial for the studied phenomenon, several methods of calculation have been applied. According to our findings, the size that corresponds to the mean size of the most representative pores is to be considered as the most reliable. It was concluded that the shape of hydrate particles replicates a host space of pores and may have a complex (e.g., fractal) shape. An attempt to simulate the curvature of hydrate particles by globular (quasi-spherical), elongated (quasi-cylindrical), or any intermediate models has been done. The quasi-spherical model seems to be more adequate for hydrate particles in small pores (
