Some current challenges in clathrate hydrate science: Nucleation, decomposition and the memory effect

Abstract

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Fully Coupled Quantum Treatment of Nanoconfined Systems: A Water Molecule inside a Fullerene C60

“…[1][2][3][4][5] Such nanoconfined systems have been the topic of broad research, focused on their different chemical and physical behavior compared with the bulk systems, as the confined molecules are subject to surrounding host medium, resulting specific unexpected effects on properties and dynamics of the guest moieties. So far, various types of nanocavities have been investigated, such as those of clathrate hydrates, [6][7][8][9][10][11][12][13][14][15] rare gas nanodroplets, [16][17][18][19][20][21] fullerenes, 22 etc.…”

Analysis of the Dissolution of CH4/CO2-Mixtures into Liquid Water and the Subsequent Hydrate Formation via In Situ Raman Spectroscopy

“…What has been shown above for CH 4 can be repeated in an identical manner for CO 2 , from which of CH 4 and CO 2 in the pure hydrate, where α = 3.13346 is the proportionality constant we obtained from the calibration measurements in different gas mixtures (see Figure 2). Figure 8 shows the temporal evolution of the molar ratio of CH 4 differs significantly from the initial one (compare Figure 5).…”

“…Gas hydrates are solid crystalline compounds consisting of hydrogen bonded water networks in which guest molecules such as methane (CH 4 ) and carbon dioxide (CO 2 ) can be incorporated [1,2]. The guest molecules thermodynamically stabilize the cage-like hydrate crystals.…”

“…The guest molecules thermodynamically stabilize the cage-like hydrate crystals. Gas hydrates form at high pressures and low temperatures, with three common hydrate structures existing in nature, known as sI, sII, and sH [3,4]. Natural gas hydrates represent a huge energy resource [5,6].…”

“…In some studies, liquid nitrogen [22] or coolant circulation [23] combined with gas chromatography were utilized for measuring gas compositions in a solid phase. Existing studies usually neglect the amount of CH 4 and CO 2 dissolved in the liquid water-rich phase, which after hydrate formation usually coexists with the solid hydrate phase. Holzammer et al found that synthetically formed gas hydrates are rather gels or slurries that contain significant inclusions of a liquid water-rich phase.…”