RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL
It is well known that methane hydrate undergoes several phase transformations at high pressures. At room temperature and low to moderate pressure, methane and water form a stable cubic structure I (sI) hydrate that is also known as MH-I. The structure is transformed to a hexagonal phase (sH/MH-II) a...
Main Authors: | , , , , |
---|---|
Other Authors: | |
Format: | Text |
Language: | English |
Subjects: | |
Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.504.2548 |
id |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.504.2548 |
---|---|
record_format |
openpolar |
spelling |
ftciteseerx:oai:CiteSeerX.psu:10.1.1.504.2548 2023-05-15T17:11:42+02:00 RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL Robin Susilo Dennis D Klug John A Ripmeester Serge Desgreniers Peter Englezos The Pennsylvania State University CiteSeerX Archives application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.504.2548 en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.504.2548 Metadata may be used without restrictions as long as the oai identifier remains attached to it. https://circle.ubc.ca/bitstream/handle/2429/1025/5474.pdf;jsessionid=CE1E976ABB8BB269BBB94E677CE05897?sequence=1 Structure H hydrate high pressure methane TBME text ftciteseerx 2016-01-08T09:17:14Z It is well known that methane hydrate undergoes several phase transformations at high pressures. At room temperature and low to moderate pressure, methane and water form a stable cubic structure I (sI) hydrate that is also known as MH-I. The structure is transformed to a hexagonal phase (sH/MH-II) above 1.0GPa. Another phase transformation occurs above 1.9GPa where the filled ice structure (MH-III) is stable up to 40 GPa before a new high pressure phase transition occurs. Experiments at such high pressures have to be performed in a diamond anvil cell (DAC). Our main interest, though, is to form sH methane hydrate at a lower pressure than reported in previous studies but with some methane in the large cages consequently increasing the methane content. This can be accomplished by introducing the molecules of the large hydrate forming substance (tert-butyl methyl ether/TBME) at a concentration slightly below the stoichiometric amount as suggested by molecular dynamics simulations. In this study we have synthesized mixed methane hydrate of sI and sH and loaded the clathrate with methane into several DACs. Raman spectra were collected at room temperature and pressures in the range of 0.1 to 11.3 GPa. The existence of sH methane hydrate was observed down to 0.2 GPa. However, the existence of methane in the large cages was visible only at pressure higher than 1.0 GPa. The excess methane in the system apparently destabilizes the sH clathrate at pressure below 1.0 GPa as it transforms to sI clathrate. Text Methane hydrate Unknown Anvil ENVELOPE(-64.267,-64.267,-65.239,-65.239) |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
ftciteseerx |
language |
English |
topic |
Structure H hydrate high pressure methane TBME |
spellingShingle |
Structure H hydrate high pressure methane TBME Robin Susilo Dennis D Klug John A Ripmeester Serge Desgreniers Peter Englezos RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL |
topic_facet |
Structure H hydrate high pressure methane TBME |
description |
It is well known that methane hydrate undergoes several phase transformations at high pressures. At room temperature and low to moderate pressure, methane and water form a stable cubic structure I (sI) hydrate that is also known as MH-I. The structure is transformed to a hexagonal phase (sH/MH-II) above 1.0GPa. Another phase transformation occurs above 1.9GPa where the filled ice structure (MH-III) is stable up to 40 GPa before a new high pressure phase transition occurs. Experiments at such high pressures have to be performed in a diamond anvil cell (DAC). Our main interest, though, is to form sH methane hydrate at a lower pressure than reported in previous studies but with some methane in the large cages consequently increasing the methane content. This can be accomplished by introducing the molecules of the large hydrate forming substance (tert-butyl methyl ether/TBME) at a concentration slightly below the stoichiometric amount as suggested by molecular dynamics simulations. In this study we have synthesized mixed methane hydrate of sI and sH and loaded the clathrate with methane into several DACs. Raman spectra were collected at room temperature and pressures in the range of 0.1 to 11.3 GPa. The existence of sH methane hydrate was observed down to 0.2 GPa. However, the existence of methane in the large cages was visible only at pressure higher than 1.0 GPa. The excess methane in the system apparently destabilizes the sH clathrate at pressure below 1.0 GPa as it transforms to sI clathrate. |
author2 |
The Pennsylvania State University CiteSeerX Archives |
format |
Text |
author |
Robin Susilo Dennis D Klug John A Ripmeester Serge Desgreniers Peter Englezos |
author_facet |
Robin Susilo Dennis D Klug John A Ripmeester Serge Desgreniers Peter Englezos |
author_sort |
Robin Susilo |
title |
RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL |
title_short |
RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL |
title_full |
RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL |
title_fullStr |
RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL |
title_full_unstemmed |
RAMAN STUDY OF THE METHANE + TBME MIXED HYDRATE IN A DIAMOND ANVIL CELL |
title_sort |
raman study of the methane + tbme mixed hydrate in a diamond anvil cell |
url |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.504.2548 |
long_lat |
ENVELOPE(-64.267,-64.267,-65.239,-65.239) |
geographic |
Anvil |
geographic_facet |
Anvil |
genre |
Methane hydrate |
genre_facet |
Methane hydrate |
op_source |
https://circle.ubc.ca/bitstream/handle/2429/1025/5474.pdf;jsessionid=CE1E976ABB8BB269BBB94E677CE05897?sequence=1 |
op_relation |
http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.504.2548 |
op_rights |
Metadata may be used without restrictions as long as the oai identifier remains attached to it. |
_version_ |
1766068470231859200 |