Professor Youngjune Park research team identifies how neopentyl alcohol guest molecule forms sI or sII hydrate depending on the binary gaseous guest molecules
Professor Youngjune Park research team identifies how neopentyl alcohol guest molecule forms sI or sII hydrate depending on the binary gaseous guest molecules
□ Professor Youngjune Park of the School of Earth Sciences and Environmental Engineering at the Gwangju Institute of Science and Technology (GIST, President Seung Hyeon Moon) has clarified the structural change according to the object molecule in multi-object hydrate * system including neopentyl alcohol (NPA).
* Hydrate: An inclusion compound in which gas is trapped in a lattice structure formed through the hydrogen bonding of water molecules under low temperature and high pressure conditions. Natural gas hydrate, which is buried in the seabed, is attracting attention as a next generation energy source. Gas storage, transportation, and separation technology using the thermodynamic characteristics of hydrate can be applied to various fields.
∘ Generally, the hydrate formed by an artificial forming agent maintains a single structure. However, in the multi-object hydrate system, including NPA used by the research team, methane is the object molecule, sII hydrate has a cubic structure of Fd-3m as nitrogen, and si hydrate has a cubic structure of Pm-3n in the case of carbon dioxide, respectively.
∘ The researchers found that NPA molecules of diameter 7.76 Å occupy the large pores (sI-L) and (sII-L) of sI, sII hydrate, which are located in the large pores of sI and sII hydrate, overturning the conventional wisdom that it cannot enter them.
□ The researchers also found that the thermodynamic equilibrium conditions in the multi-object (methane, nitrogen, and carbon dioxide) hydrate systems, including NPA, were better than pure methane, nitrogen, and carbon dioxide hydrate.
∘ The researchers confirmed that the NPA molecule is a thermodynamic promoter that promotes the formation of hydrate by occupying the large pore (sI-L) of sI hydrate and the large pore (sII-L) of sII hydrate.
□ The researchers identified a tuning phenomenon in the sI structure carbon dioxide hydrate system, including NPA, which occupies carbon dioxide in the large pores (sI-L) according to the NPA concentration. SI The tuning phenomenon of carbon dioxide object molecules in hydrate was first reported in this study.
□ The first author of this paper, Seokyoon Moon, said, "Tuning phenomenon is expected to increase the amount of carbon dioxide stored in the carbon dioxide hydrate system, including NPA, so that it can be applied to carbon dioxide separation and storage."
