Formation of Methane Hydrate in the Presence of Natural and Synthetic Nanoparticles

Abstract

Natural gas hydrates occur widely on the ocean-bed and in permafrost regions, and have potential as an untapped energy resource. Their formation and growth, however, poses major problems for the energy sector due to their tendency to block oil and gas pipelines, whereas their melting is viewed as a potential contributor to climate change. Although recent advances have been made in understanding bulk methane hydrate formation, the effect of impurity particles, which are always present under conditions relevant to industry and the environment, remains an open question. Here we present results from neutron scattering experiments and molecular dynamics simulations that show that the formation of methane hydrate is insensitive to the addition of a wide range of impurity particles. Our analysis shows that this is due to the different chemical natures of methane and water, with methane generally excluded from the volume surrounding the nanoparticles. This has important consequences for our understanding of the mechanism of hydrate nucleation and the design of new inhibitor molecules.

Clathrate hydrates: recent advances on CH4 and CO2 hydrates, and possible new frontiers

“…Concerning the nucleation of hydrates, an important question that is being addressed by the community concerns the effect on the nucleation rate due to the proximity of mineral surfaces and the presence of impurities. Recently, Cox et al 133 combined atomistic MD simulations with neutron scattering experiments to address this question and reported no effect on hydrate nucleation due to the presence of a wide variety of nanoparticles. These results seem to be consistent with coarse-grained simulations by DeFever and Sarupria, 134 who showed that even in proximity of an interface nucleation follows a bulk-like mechanism.…”

Understanding the Pathway of Gas Hydrate Formation with Porous Materials for Enhanced Gas Separation

“…However, important questions about what kind of gaps and how they can be formed are still not clarified, because there is no valid scientific method to distinguish this type of gaps and semiclathrate in the pore, and quantitative analysis of the gas in gas hydrates or adsorptive phase is hardly carried out. Some techniques such as molecular simulations [11, 20], in situ Raman spectroscopy [21], solid-state nuclear magnetic resonance [10, 22], neutron diffraction [23, 24], and synchrotron X-ray powder diffraction [25] could only be employed to confirm that the formation of gas hydrates is dependent on porous materials. There is no doubt that gas hydrates could be formed on porous materials, but the details about the formation process and whether they are formed inside the pores or not are still ambiguous.…”

Novel cement slurry containing micro‐encapsulated phase change materials: Characterization, application and mechanism analysis

“…But, more than 70% of marine cementing faces the challenge of hydrate decomposition . Natural gas hydrates are a meta‐stable cage compound formed under low temperature and high pressure conditions, mainly distributed on the continental slope outside the continental shelf, sedimentary rock layers at the bottom of deep sea and deep lake and polar permafrost regions . Natural gas hydrates are essentially a potential new energy source, and the reserves are very large .…”

“…3,4 Natural gas hydrates are a metastable cage compound formed under low temperature and high pressure conditions, mainly distributed on the continental slope outside the continental shelf, sedimentary rock layers at the bottom of deep sea and deep lake and polar permafrost regions. [5][6][7] Natural gas hydrates are essentially a potential new energy source, and the reserves are very large. [8][9][10] However, in the development process of marine resources, hydrates put forward higher requirements for cement slurry.…”