Appendix O: Hydrate dissociation pressure

The formation of sodium disulfite by the heterogeneous reaction of solid active sodium sulfite with gaseous sulfur dioxide in the presence of water vapour was investigated over the temperature range of 293 to 393 K at SO2. H2O and O2 partial pressures of 1.2-7.4, 1.2-6.4 and 0-11.3 kPa, respectively. The effect of the reaction time was also examined. Kinetic measurements were supplemented with the determination of the equilibrium dissociation pressure of SO2 in contact with sodium sulfite at 373.15 K. The major aim of the work was to establish the optimum conditions for attaining the maximum degree of conversion of the solid reactant to sodium disulfite. The conditions for the formation of virtually pure sodium disulfite were found.

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Examination of amino acid inhibitor effect in methane hydrate dissociation via molecular dynamics simulation

Journal of Molecular Liquids ◽

10.1016/j.molliq.2020.115205 ◽

2021 ◽

Vol 325 ◽

pp. 115205

Author(s):

Yu Hu ◽

Shuai Wang ◽

Xuesong Yang ◽

Yurong He

Keyword(s):

Molecular Dynamics ◽

Amino Acid ◽

Molecular Dynamics Simulation ◽

Methane Hydrate ◽

Dynamics Simulation ◽

Hydrate Dissociation ◽

Acid Inhibitor

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Formation of a Low-Density Liquid Phase during the Dissociation of Gas Hydrates in Confined Environments

Nanomaterials ◽

10.3390/nano11030590 ◽

2021 ◽

Vol 11 (3) ◽

pp. 590

Author(s):

Lihua Wan ◽

Xiaoya Zang ◽

Juan Fu ◽

Xuebing Zhou ◽

Jingsheng Lu ◽

...

Keyword(s):

Natural Gas ◽

Methane Hydrate ◽

Phase State ◽

Solid Phase ◽

Potential Method ◽

Methane Hydrates ◽

Low Density ◽

Hydrate Dissociation ◽

State Of Water ◽

Confined Environment

The large amounts of natural gas in a dense solid phase stored in the confined environment of porous materials have become a new, potential method for storing and transporting natural gas. However, there is no experimental evidence to accurately determine the phase state of water during nanoscale gas hydrate dissociation. The results on the dissociation behavior of methane hydrates confined in a nanosilica gel and the contained water phase state during hydrate dissociation at temperatures below the ice point and under atmospheric pressure are presented. Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (PXRD) were used to trace the dissociation of confined methane hydrate synthesized from pore water confined inside the nanosilica gel. The characterization of the confined methane hydrate was also analyzed by PXRD. It was found that the confined methane hydrates dissociated into ultra viscous low-density liquid water (LDL) and methane gas. The results showed that the mechanism of confined methane hydrate dissociation at temperatures below the ice point depended on the phase state of water during hydrate dissociation.

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