Journal ArticleDOI
Growth Kinetics and Gas Diffusion in Formation of Gas Hydrates from Ice
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TLDR
In this article, high-resolution measurements for gas hydrate formation from ice spheres by X-ray computed tomography are reported, which can be accurately and directly quantified from micro-scale measurements, resulting in new estimates for the intrinsic reaction rate constant and effective diffusion coefficient of xenon in the hydrate.Abstract:
Clathrate
hydrates are ubiquitous in deep-sea sediments and the
permafrost on earth, as well as abundant in interstellar environments.
Despite many potential applications of gas hydrates for gas storage/transportation,
carbon sequestration, and water treatment, the fundamental mechanism
for gas hydrate nucleation and growth are still poorly understood
due to the difficulty in spatial and temporal measurements that can
probe specific structural properties. Here, high resolution measurements
for xenon hydrate formation from ice spheres by X-ray computed tomography
are reported. For the first time, the nucleation and growth of hydrates
can be accurately and directly quantified from microscale measurements,
resulting in new estimates for the intrinsic reaction rate constant
of xenon hydrate formation, and the effective diffusion coefficient
of xenon in the hydrate. The measured activation energy of hydrate
formation is 71.11 kJ/mol and the diffusivity of xenon in hydrate
ranges from 2.8 × 10–15 to 4.3 × 10–14 m2/s. These results are of fundamental
value in developing a comprehensive understanding on the mechanism
of gas hydrate formation, which is essential in their application
for energy solutions and increasingly important in astrophysical science.read more
Citations
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Formation of porous gas hydrates from ice powders: Diffraction experiments and multistage model
TL;DR: In this article, the formation of porous gas hydrates from deuterated ice Ih powders was examined by electron microscopy and found to have a submicron porous structure.
Journal ArticleDOI
New Approach for Determining the Reaction Rate Constant of Hydrate Formation via X-ray Computed Tomography
TL;DR: In this article, the authors proposed a method for gas hydrates as a medium for energy storage and transport, gas separation, and carbon dioxide sequestration, which attracted substantial attention in energy and environmental research.
Journal ArticleDOI
Characterizing Mass-Transfer mechanism during gas hydrate formation from water droplets
Z Weng,Liang Huiyong,Dawei Guan,Lauren M. Schmitt,Kangji Shi,Lei Yang,Lunxiang Zhang,Jiafei Zhao,Yongchen Song +8 more
TL;DR: In this article, the mass transfer characteristics of water and guest molecules across hydrate shells during their formation from water droplets were investigated using X-ray computed tomography to reveal the transport mechanism in hydrates.
Journal ArticleDOI
Characterizing Mass-Transfer mechanism during gas hydrate formation from water droplets
Z Weng,Lauren M. Schmitt +1 more
TL;DR: In this article , the mass transfer characteristics of water and guest molecules across hydrate shells during their formation from water droplets were investigated using X-ray computed tomography to reveal the transport mechanism in hydrates.
Journal ArticleDOI
Reduced phase stability and faster formation/dissociation kinetics in confined methane hydrate.
Dongliang Jin,Benoit Coasne +1 more
TL;DR: The metastability barrier upon hydrate formation and dissociation is found to decrease upon confinement, therefore providing a molecular-scale picture for the faster kinetics observed in experiments on confined gas hydrates.
References
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Journal ArticleDOI
Fundamental principles and applications of natural gas hydrates
TL;DR: Natural gas hydrates have an important bearing on flow assurance and safety issues in oil and gas pipelines, they offer a largely unexploited means of energy recovery and transportation, and could play a significant role in past and future climate change.
Journal ArticleDOI
Gas hydrates—geological perspective and global change
TL;DR: In this article, the authors discuss three important aspects of gas hydrates: their potential as a fossil fuel resource, their role as a submarine geohazard, and their effects on global climate change.
Journal ArticleDOI
Tuning clathrate hydrates for hydrogen storage
Huen Lee,Jongwon Lee,Do Youn Kim,Jeasung Park,Yutaek Seo,Huang Zeng,Igor L. Moudrakovski,Christopher I. Ratcliffe,John A. Ripmeester +8 more
TL;DR: Hydrogen storage capacities in THF-containing binary-clathrate hydrates can be increased to ∼4 wt% at modest pressures by tuning their composition to allow the hydrogen guests to enter both the larger and the smaller cages, while retaining low-pressure stability.
Journal ArticleDOI
A kinetic study of methane hydrate formation
A. Vysniauskas,P.R. Bishnoi +1 more
TL;DR: In this paper, a semi-empirical model was formulated to correlate the experimental kinetic data, which revealed that the formation kinetics were dependent on the interfacial area, pressure, temperature and degree of supercooling.
Journal ArticleDOI
A new approach to gas hydrate modelling
Guang-Jin Chen,Tian-Min Guo +1 more
TL;DR: In this paper, a two-step hydrate formation mechanism is proposed for gas hydrate, which consists of a quasi-chemical reaction process to form basic hydrate and an adsorption process of smaller gas molecules in the linked cavities of basic hydrates.