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Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates

Knowledge of carbon isotope fractionation is needed in order to discuss the formation and dissociation of naturally occurring CO(2) hydrates. We investigated carbon isotope fractionation during CO(2) hydrate formation and measured the three-phase equilibria of (12)CO(2)–H(2)O and (13)CO(2)–H(2)O sys...

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Autores principales: Kimura, Hiromi, Fuseya, Go, Takeya, Satoshi, Hachikubo, Akihiro
Formato: Online Artículo Texto
Lenguaje:English
Publicado: MDPI 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8306263/
https://www.ncbi.nlm.nih.gov/pubmed/34299489
http://dx.doi.org/10.3390/molecules26144215
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author Kimura, Hiromi
Fuseya, Go
Takeya, Satoshi
Hachikubo, Akihiro
author_facet Kimura, Hiromi
Fuseya, Go
Takeya, Satoshi
Hachikubo, Akihiro
author_sort Kimura, Hiromi
collection PubMed
description Knowledge of carbon isotope fractionation is needed in order to discuss the formation and dissociation of naturally occurring CO(2) hydrates. We investigated carbon isotope fractionation during CO(2) hydrate formation and measured the three-phase equilibria of (12)CO(2)–H(2)O and (13)CO(2)–H(2)O systems. From a crystal structure viewpoint, the difference in the Raman spectra of hydrate-bound (12)CO(2) and (13)CO(2) was revealed, although their unit cell size was similar. The δ(13)C of hydrate-bound CO(2) was lower than that of the residual CO(2) (1.0–1.5‰) in a formation temperature ranging between 226 K and 278 K. The results show that the small difference between equilibrium pressures of ~0.01 MPa in (12)CO(2) and (13)CO(2) hydrates causes carbon isotope fractionation of ~1‰. However, the difference between equilibrium pressures in the (12)CO(2)–H(2)O and (13)CO(2)–H(2)O systems was smaller than the standard uncertainties of measurement; more accurate pressure measurement is required for quantitative discussion.
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spelling pubmed-83062632021-07-25 Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates Kimura, Hiromi Fuseya, Go Takeya, Satoshi Hachikubo, Akihiro Molecules Article Knowledge of carbon isotope fractionation is needed in order to discuss the formation and dissociation of naturally occurring CO(2) hydrates. We investigated carbon isotope fractionation during CO(2) hydrate formation and measured the three-phase equilibria of (12)CO(2)–H(2)O and (13)CO(2)–H(2)O systems. From a crystal structure viewpoint, the difference in the Raman spectra of hydrate-bound (12)CO(2) and (13)CO(2) was revealed, although their unit cell size was similar. The δ(13)C of hydrate-bound CO(2) was lower than that of the residual CO(2) (1.0–1.5‰) in a formation temperature ranging between 226 K and 278 K. The results show that the small difference between equilibrium pressures of ~0.01 MPa in (12)CO(2) and (13)CO(2) hydrates causes carbon isotope fractionation of ~1‰. However, the difference between equilibrium pressures in the (12)CO(2)–H(2)O and (13)CO(2)–H(2)O systems was smaller than the standard uncertainties of measurement; more accurate pressure measurement is required for quantitative discussion. MDPI 2021-07-11 /pmc/articles/PMC8306263/ /pubmed/34299489 http://dx.doi.org/10.3390/molecules26144215 Text en © 2021 by the authors. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
spellingShingle Article
Kimura, Hiromi
Fuseya, Go
Takeya, Satoshi
Hachikubo, Akihiro
Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates
title Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates
title_full Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates
title_fullStr Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates
title_full_unstemmed Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates
title_short Carbon Isotope Fractionation during the Formation of CO(2) Hydrate and Equilibrium Pressures of (12)CO(2) and (13)CO(2) Hydrates
title_sort carbon isotope fractionation during the formation of co(2) hydrate and equilibrium pressures of (12)co(2) and (13)co(2) hydrates
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8306263/
https://www.ncbi.nlm.nih.gov/pubmed/34299489
http://dx.doi.org/10.3390/molecules26144215
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