1
|
Kummamuru NB, Ciocarlan RG, Houlleberghs M, Martens J, Breynaert E, Verbruggen SW, Cool P, Perreault P. Surface modification of mesostructured cellular foam to enhance hydrogen storage in binary THF/H 2 clathrate hydrate. SUSTAINABLE ENERGY & FUELS 2024; 8:2824-2838. [PMID: 38933237 PMCID: PMC11197926 DOI: 10.1039/d4se00114a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 04/12/2024] [Indexed: 06/28/2024]
Abstract
This study introduces solid-state tuning of a mesostructured cellular foam (MCF) to enhance hydrogen (H2) storage in clathrate hydrates. Grafting of promoter-like molecules (e.g., tetrahydrofuran) at the internal surface of the MCF resulted in a substantial improvement in the kinetics of formation of binary H2-THF clathrate hydrate. Identification of the confined hydrate as sII clathrate hydrate and enclathration of H2 in its small cages was performed using XRD and high-pressure 1H NMR spectroscopy respectively. Experimental findings show that modified MCF materials exhibit a ∼1.3 times higher H2 storage capacity as compared to non-modified MCF under the same conditions (7 MPa, 265 K, 100% pore volume saturation with a 5.56 mol% THF solution). The enhancement in H2 storage is attributed to the hydrophobicity originating from grafting organic molecules onto pristine MCF, thereby influencing water interactions and fostering an environment conducive to H2 enclathration. Gas uptake curves indicate an optimal tuning point for higher H2 storage, favoring a lower density of carbon per nm2. Furthermore, a direct correlation emerges between higher driving forces and increased H2 storage capacity, culminating at 0.52 wt% (46.77 mmoles of H2 per mole of H2O and 39.78% water-to-hydrate conversions) at 262 K for the modified MCF material with fewer carbons per nm2. Notably, the substantial H2 storage capacity achieved without energy-intensive processes underscores solid-state tuning's potential for H2 storage in the synthesized hydrates. This study evaluated two distinct kinetic models to describe hydrate growth in MCF. The multistage kinetic model showed better predictive capabilities for experimental data and maintained a low average absolute deviation. This research provides valuable insights into augmenting H2 storage capabilities and holds promising implications for future advancements.
Collapse
Affiliation(s)
- Nithin B Kummamuru
- Sustainable Energy Air & Water Technology (DuEL), Department of Bioscience Engineering, University of Antwerp Groenenborgerlaan 171 2020 Antwerpen Belgium
- Laboratory for the Electrification of Chemical Processes and Hydrogen (ElectrifHy), University of Antwerp Olieweg 97 2020 Antwerp Belgium
| | - Radu-George Ciocarlan
- Department of Chemistry, University of Antwerp Universiteitsplein 1 2610 Wilrijk Belgium
| | - Maarten Houlleberghs
- KU Leuven, Centre for Surface Chemistry and Catalysis-Characterization and Application Team (COK-KAT) Celestijnenlaan 200F - Box 2461 Leuven 3001 Belgium
| | - Johan Martens
- KU Leuven, Centre for Surface Chemistry and Catalysis-Characterization and Application Team (COK-KAT) Celestijnenlaan 200F - Box 2461 Leuven 3001 Belgium
- NMR/X-Ray Platform for Convergence Research (NMRCoRe) Celestijnenlaan 200F - Box 2461 Leuven 3001 Belgium
| | - Eric Breynaert
- KU Leuven, Centre for Surface Chemistry and Catalysis-Characterization and Application Team (COK-KAT) Celestijnenlaan 200F - Box 2461 Leuven 3001 Belgium
- NMR/X-Ray Platform for Convergence Research (NMRCoRe) Celestijnenlaan 200F - Box 2461 Leuven 3001 Belgium
| | - Sammy W Verbruggen
- Sustainable Energy Air & Water Technology (DuEL), Department of Bioscience Engineering, University of Antwerp Groenenborgerlaan 171 2020 Antwerpen Belgium
- NANOlab Center of Excellence, University of Antwerp Groenenborgerlaan 171 2020 Antwerpen Belgium
| | - Pegie Cool
- Department of Chemistry, University of Antwerp Universiteitsplein 1 2610 Wilrijk Belgium
| | - Patrice Perreault
- Laboratory for the Electrification of Chemical Processes and Hydrogen (ElectrifHy), University of Antwerp Olieweg 97 2020 Antwerp Belgium
- University of Antwerp, BlueApp Olieweg 97 2020 Antwerpen Belgium
| |
Collapse
|
2
|
Alavi S, Moudrakovski IL, Ratcliffe CI, Ripmeester JA. Unusual species of methane hydrate detected in nanoporous media using solid state 13C NMR. J Chem Phys 2024; 160:214709. [PMID: 38832748 DOI: 10.1063/5.0204109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Accepted: 05/14/2024] [Indexed: 06/05/2024] Open
Abstract
Methane is considered to be a cubic structure I (CS-I) clathrate hydrate former, although in a number of instances, small amounts of structure II (CS-II) clathrate hydrate have been transiently observed as well. In this work, solid-state magic angle spinning 13C NMR spectra of methane hydrate formed at low temperatures inside silica-based nanoporous materials with pores in the range of 3.8-20.0 nm (CPG-20, Vycor, and MCM-41) show methane in several different environments. In addition to methane encapsulated in the dodecahedral 512 (D) and tetrakaidecahedral 51262 (T) cages typical of the CS-I clathrate hydrate phase, methane guests in pentakaidecahedral 51263 (P) and hexakaidecahedral 51264 (H) cages are also identified, and these appear to be stabilized for extended periods of time. The ratio of methane guests among the D and T cages determined from the line intensities is significantly different from that of bulk CS-I samples and indicates that both CS-I and CS-II are present as the dominant species. This is the first observation of methane in P cages, and the possible structures in which they could be present are discussed. Broad and relatively strong methane peaks, which are also observed in the spectra, can be related to methane dissolved in an amorphous component of water adjacent to the pore walls. Nanoconfinement and interaction with the pore walls clearly have a strong influence on the hydrate formed and may reflect species present in the early stages of hydrate growth.
Collapse
Affiliation(s)
- Saman Alavi
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Igor L Moudrakovski
- Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart, Germany
| | | | - John A Ripmeester
- National Research Council of Canada, 100 Sussex Dr., Ottawa, Ontario K1N 5A2, Canada
| |
Collapse
|
3
|
Cao P, Wu J, Ning F. Mechanical properties of amorphous CO 2 hydrates: insights from molecular simulations. Phys Chem Chem Phys 2024; 26:9388-9398. [PMID: 38444360 DOI: 10.1039/d4cp00203b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2024]
Abstract
Understanding physicochemical properties of amorphous gas hydrate systems is of great significance to reveal structural stabilities of polycrystalline gas hydrate systems. Furthermore, amorphous gas hydrates can occur ordinarily in the nucleation events of gas hydrate systems. Herein, the mechanical properties of amorphous carbon dioxide hydrates are examined by means of all-atom classical molecular dynamic simulations. Our molecular simulation results reveal that mechanical strengths of amorphous carbon dioxide hydrates are evidently governed by temperatures, confining pressures, and ratios of water to carbon dioxide molecules. Notably, under compressive loads, amorphous carbon dioxide hydrates firstly exhibit monotonic strain hardening, followed by an interesting distinct phenomenon characterized by a steady flow stress at further large deformation strains. Furthermore, structural evolutions of amorphous carbon dioxide hydrates are analyzed on the basis of the N-Hbond DOP order parameter. These important findings can not only contribute to our understanding of the structural stabilities of amorphous gas hydrate systems, but also help to develop fundamental understandings about grain boundaries of gas hydrate systems.
Collapse
Affiliation(s)
- Pinqiang Cao
- School of Resource and Environmental Engineering, Wuhan University of Science and Technology, Wuhan, Hubei 430081, China.
| | - Jianyang Wu
- Department of Physics, Research Institute for Biomimetics and Soft Matter, Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, China.
| | - Fulong Ning
- Faculty of Engineering, China University of Geosciences, Wuhan, Hubei 430074, China.
| |
Collapse
|
4
|
Xue H, Li L, Wang Y, Lu Y, Cui K, He Z, Bai G, Liu J, Zhou X, Wang J. Probing the critical nucleus size in tetrahydrofuran clathrate hydrate formation using surface-anchored nanoparticles. Nat Commun 2024; 15:157. [PMID: 38167854 PMCID: PMC10762117 DOI: 10.1038/s41467-023-44378-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Accepted: 12/11/2023] [Indexed: 01/05/2024] Open
Abstract
Controlling the formation of clathrate hydrates is crucial for advancing hydrate-based technologies. However, the microscopic mechanism underlying clathrate hydrate formation through nucleation remains poorly elucidated. Specifically, the critical nucleus, theorized as a pivotal step in nucleation, lacks empirical validation. Here, we report uniform nanoparticles, e.g., graphene oxide (GO) nanosheets and gold or silver nanocubes with controlled sizes, as nanoprobes to experimentally measure the size of the critical nucleus of tetrahydrofuran (THF) clathrate hydrate formation. The capability of the nanoparticles in facilitating THF clathrate hydrate nucleation displays generally an abrupt change at a nanoparticle-size-determined specific supercooling. It is revealed that the free-energy barrier shows an abrupt change when the nanoparticles have an approximately the same size as that of the critical nucleus. Thus, it is inferred that THF clathrate hydrate nucleation involves the creation of a critical nucleus with its size being inversely proportional to the supercooling. By proving the existence and determining the supercooling-dependent size of the critical nucleus of the THF clathrate hydrates, this work brings insights in the microscopic pictures of the clathrate hydrate nucleation.
Collapse
Affiliation(s)
- Han Xue
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Linhai Li
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Yiqun Wang
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Youhua Lu
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Kai Cui
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Zhiyuan He
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Guoying Bai
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Jie Liu
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Xin Zhou
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
- Wenzhou Institute, University of Chinese Academy of Sciences, Wenzhou, 325001, China.
| | - Jianjun Wang
- Beijing National Laboratory for Molecular Science, Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
- Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.
| |
Collapse
|
5
|
Guerra A, Mathews S, Su JT, Marić M, Servio P, Rey AD. Molecular dynamics predictions of transport properties for carbon dioxide hydrates under pre-nucleation conditions using TIP4P/Ice water and EPM2, TraPPE, and Zhang carbon dioxide potentials. J Mol Liq 2023. [DOI: 10.1016/j.molliq.2023.121674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
|
6
|
Cao P. Structural Stability Evolutions of CH4 and CO2 Hydrate-Sand Nanoparticle Systems. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.121041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
7
|
Wang L, Dou M, Wang Y, Xu Y, Li Y, Chen Y, Li L. A Review of the Effect of Porous Media on Gas Hydrate Formation. ACS OMEGA 2022; 7:33666-33679. [PMID: 36188251 PMCID: PMC9520562 DOI: 10.1021/acsomega.2c03048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 09/02/2022] [Indexed: 05/27/2023]
Abstract
Most gas hydrates on the earth are in sediments and permafrost areas, and porous media are often used industrially as additives to improve gas hydrate formation. For further understanding its exploration and exploitation under natural conditions and its application in industry, it is necessary to study the effect of porous media on hydrate formation. The results show that the stacked porous media affects the phase equilibrium of hydrate formation depending on the competition water activity and large specific surface areas, while integrated porous media, such as metal foam, can transfer the hydration heat rapidly and moderate the hydrate phase equilibrium. A supersaturated metal-organic framework is able to significantly improve gas storage performance and can be used as a new material to promote hydrate formation. However, the critical particle size should be studied further for approaching the best promotion effect. In addition, together with the kinetic accelerators, porous media has a synergistic effect on gas hydrate formation. The carboxyl and hydroxyl groups on the surface of porous media can stabilize hydrate crystals through hydrogen bonding. However, the hydroxyl radicals on the silica surface inhibit the combination of CH4 and free water, making the phase equilibrium conditions more demanding.
Collapse
Affiliation(s)
- Lanyun Wang
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
- Collaborative
Innovation Center for coal Safety Production & high-efficient-clean
utilization for coal by Provincial and Ministerial Co-construction, Jiaozuo 454003, China
- State
Key Laboratory Cultivation Base for Gas Geology and Gas Control in
Henan Polytechnic University, Jiaozuo 454003, China
| | - Mengyue Dou
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
| | - Yan Wang
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
- Collaborative
Innovation Center for coal Safety Production & high-efficient-clean
utilization for coal by Provincial and Ministerial Co-construction, Jiaozuo 454003, China
- State
Key Laboratory Cultivation Base for Gas Geology and Gas Control in
Henan Polytechnic University, Jiaozuo 454003, China
| | - Yongliang Xu
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
- Collaborative
Innovation Center for coal Safety Production & high-efficient-clean
utilization for coal by Provincial and Ministerial Co-construction, Jiaozuo 454003, China
- State
Key Laboratory Cultivation Base for Gas Geology and Gas Control in
Henan Polytechnic University, Jiaozuo 454003, China
| | - Yao Li
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
- Collaborative
Innovation Center for coal Safety Production & high-efficient-clean
utilization for coal by Provincial and Ministerial Co-construction, Jiaozuo 454003, China
- State
Key Laboratory Cultivation Base for Gas Geology and Gas Control in
Henan Polytechnic University, Jiaozuo 454003, China
| | - Yu Chen
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
| | - Lingshuang Li
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
| |
Collapse
|
8
|
Nguyen NN, Nguyen AV. "Nanoreactors" for Boosting Gas Hydrate Formation toward Energy Storage Applications. ACS NANO 2022; 16:11504-11515. [PMID: 35939085 DOI: 10.1021/acsnano.2c04640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Hydrogen and methane can be molecularly incorporated in ice-like water structures up to mass fractions of 4.3% and 13.3%, respectively. The resulting solid structures, called gas hydrates, offer great potential for the efficient storage of hydrogen and natural gas. However, slow gas encapsulation by bulk water hinders this application. Porous structures have been shown to effectively promote gas hydrate formation and are a potential enabler for the development of hydrate-based gas storage technologies. Here, we offer an insightful perspective on using porous structures as nanoreactors for achieving fast gas hydrate formation for gas storage applications. We critically discuss and elucidate the working mechanisms of nanoreactors and identify the criteria for efficient nanoreactors. Based on the concepts founded, we propose a theoretical framework for designing next-generation porous materials for delivering better promoting effects on gas hydrate formation.
Collapse
Affiliation(s)
- Ngoc N Nguyen
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Anh V Nguyen
- School of Chemical Engineering, The University of Queensland, Brisbane, QLD 4072, Australia
| |
Collapse
|
9
|
Guerra A, Mathews S, Marić M, Servio P, Rey AD. All-Atom Molecular Dynamics of Pure Water-Methane Gas Hydrate Systems under Pre-Nucleation Conditions: A Direct Comparison between Experiments and Simulations of Transport Properties for the Tip4p/Ice Water Model. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27155019. [PMID: 35956968 PMCID: PMC9370622 DOI: 10.3390/molecules27155019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 07/29/2022] [Accepted: 08/02/2022] [Indexed: 11/24/2022]
Abstract
(1) Background: New technologies involving gas hydrates under pre-nucleation conditions such as gas separations and storage have become more prominent. This has necessitated the characterization and modeling of the transport properties of such systems. (2) Methodology: This work explored methane hydrate systems under pre-nucleation conditions. All-atom molecular dynamics simulations were used to quantify the performance of the TIP4P/2005 and TIP4P/Ice water models to predict the viscosity, diffusivity, and thermal conductivity using various formulations. (3) Results: Molecular simulation equilibrium was robustly demonstrated using various measures. The Green–Kubo estimation of viscosity outperformed other formulations when combined with TIP4P/Ice, and the same combination outperformed all TIP4P/2005 formulations. The Green–Kubo TIP4P/Ice estimation of viscosity overestimates (by 84% on average) the viscosity of methane hydrate systems under pre-nucleation conditions across all pressures considered (0–5 MPag). The presence of methane was found to increase the average number of hydrogen bonds over time (6.7–7.8%). TIP4P/Ice methane systems were also found to have 16–19% longer hydrogen bond lifetimes over pure water systems. (4) Conclusion: An inherent limitation in the current water force field for its application in the context of transport properties estimations for methane gas hydrate systems. A re-parametrization of the current force field is suggested as a starting point. Until then, this work may serve as a characterization of the deviance in viscosity prediction.
Collapse
|
10
|
Liu Y, Sun J, Chen C, Li W, Qin Y, Wang Y. Molecular insights into gas hydrate formation in the presence of graphene oxide solid surfaces. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.119309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
11
|
An Integrated Experimental and Computational Platform to Explore Gas Hydrate Promotion, Inhibition, Rheology, and Mechanical Properties at McGill University: A Review. ENERGIES 2022. [DOI: 10.3390/en15155532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
(1) Background: Gas hydrates are historically notable due to their prevalence and influence on operational difficulties in the oil and gas industry. Recently, new technologies involving the formation of gas hydrates to accomplish various applications have been proposed. This has created new motivation for the characterization of rheological and mechanical properties and the study of molecular phenomena in gas hydrates systems, particularly in the absence of oil and under pre-nucleation conditions. (2) Methodology: This work reviews advances in research on the promotion, inhibition, rheology, and mechanical properties of gas hydrates obtained through an integrated material synthesis-property characterization-multi-scale theoretical and computational platform at McGill University. (3) Discussion: This work highlights the findings from previous experimental work by our group and identifies some of their inherent physical limitations. The role of computational research methods in extending experimental results and observations in the context of mechanical properties of gas hydrates is presented. (4) Summary and Future perspective: Experimental limitations due to the length and time scales of physical phenomena associated with gas hydrates were identified, and future steps implementing the integrated experimental-computational platform to address the limitations presented here were outlined.
Collapse
|
12
|
Mathews S, Daghash S, Rey A, Servio P. Recent Advances in Density Functional Theory and Molecular Dynamics Simulation of Mechanical, Interfacial, and Thermal Properties of Natural Gas Hydrates in Canada. CAN J CHEM ENG 2022. [DOI: 10.1002/cjce.24516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Samuel Mathews
- Department of Chemical Engineering McGill University Montréal Québec Canada
| | - Shaden Daghash
- Department of Chemical Engineering McGill University Montréal Québec Canada
| | - Alejandro Rey
- Department of Chemical Engineering McGill University Montréal Québec Canada
| | - Phillip Servio
- Department of Chemical Engineering McGill University Montréal Québec Canada
| |
Collapse
|
13
|
A review of clathrate hydrate nucleation, growth and decomposition studied using molecular dynamics simulation. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2021.118025] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
14
|
Moon H, Collanton RP, Monroe JI, Casey TM, Shell MS, Han S, Scott SL. Evidence for Entropically Controlled Interfacial Hydration in Mesoporous Organosilicas. J Am Chem Soc 2022; 144:1766-1777. [PMID: 35041412 DOI: 10.1021/jacs.1c11342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
At aqueous interfaces, the distribution and dynamics of adsorbates are modulated by the behavior of interfacial water. Hydration of a hydrophobic surface can store entropy via the ordering of interfacial water, which contributes to the Gibbs energy of solute binding. However, there is little experimental evidence for the existence of such entropic reservoirs, and virtually no precedent for their rational design in systems involving extended interfaces. In this study, two series of mesoporous silicas were modified in distinct ways: (1) progressively deeper thermal dehydroxylation, via condensation of surface silanols, and (2) increasing incorporation of nonpolar organic linkers into the silica framework. Both approaches result in decreasing average surface polarity, manifested in a blue-shift in the fluorescence of an adsorbed dye. For the inorganic silicas, hydrogen-bonding of water becomes less extensive as the number of surface silanols decreases. Overhauser dynamic nuclear polarization (ODNP) relaxometry indicates enhanced surface water diffusivity, reflecting a loss of enthalpic hydration. In contrast, organosilicas show a monotonic decrease in surface water diffusivity with decreasing polarity, reflecting enhanced hydrophobic hydration. Molecular dynamics simulations predict increased tetrahedrality of interfacial water for the organosilicas, implying increased ordering near the nm-size organic domains (relative to inorganic silicas, which necessarily lack such domains). These findings validate the prediction that hydrophobic hydration at interfaces is controlled by the microscopic length scale of the hydrophobic regions. They further suggest that the hydration thermodynamics of structurally heterogeneous silica surfaces can be tuned to promote adsorption, which in turn tunes the selectivity in catalytic reactions.
Collapse
Affiliation(s)
- Hyunjin Moon
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Ryan P Collanton
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Jacob I Monroe
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Thomas M Casey
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States.,Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Susannah L Scott
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States.,Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| |
Collapse
|
15
|
Lv X, Zhang J, Zhao Y, Liu Y, Xu J, Ma Q, Song S, Zhou S. Experimental Study of the Growth Kinetics of Natural Gas Hydrates in an Oil-Water Emulsion System. ACS OMEGA 2022; 7:599-616. [PMID: 35036727 PMCID: PMC8757353 DOI: 10.1021/acsomega.1c05127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/09/2021] [Indexed: 06/14/2023]
Abstract
In order to explore the growth kinetics characteristics of NGH (natural gas hydrate) in an oil and gas mixed transportation pipeline and ensure the safe transportation of the pipeline, with the high-pressure hydrate experimental loop, an experimental study on the growth characteristics of NGH in an oil-water emulsion system was carried out, and the effects of pressure, flow rate, and water cut on the hydrate induction time, gas consumption, consumption rate, and hydrate volume fraction were explored, and important experimental rules were obtained. The experiment was divided into three stages: in the rapid formation stage of the hydrate, the temperature and gas consumption rose sharply, and the pressure dropped suddenly. The induction time decreased with the increase of pressure, flow rate, and water cut. The induction time of 6 MPa was 86.13 min, which was shortened by 39.68% compared with the induction time of 142.8 min of 5 MPa. The induction time of 1500 kg/h was 88.27 min, which was shorter by 13.91% than that 102.53 min of 550 kg/h. The induction time of 20% water cut was 58.53 min, which was shorter by 13.99% than that 68.4 min of 15% water cut. The gas consumption and hydrate volume fraction were both increased with the increase of pressure and water cut and decreased with the increase in the flow rate. In the whole process of the formation of NGH, the consumption rate first increased and then decreased. The pressure-drop and apparent viscosity increased with the increase of hydrate volume fraction in a certain range. The sensitivity analysis of hydrate induction time based on the standard regression coefficient method showed that the initial pressure played a major role, followed by the flow rate and the water cut. Based on the sensitivity analysis of hydrate volume fraction by the gray correlation method, it was found that the hydrate volume fraction had the closest relationship with the initial pressure, followed by the flow rate and the water cut. Finally, the empirical formulas of induction time and hydrate volume fraction in an oil-water emulsion system were established.
Collapse
Affiliation(s)
- Xiaofang Lv
- Jiangsu
Key Laboratory of Oil and Gas Storage & Transportation Technology, Changzhou University, Changzhou 213016, China
- China
Petroleum & Chemical Corporation Northwest Oilfield Branch, Petroleum Engineering Technology Research Institute, Urumqi 830011, China
| | - Jie Zhang
- Jiangsu
Key Laboratory of Oil and Gas Storage & Transportation Technology, Changzhou University, Changzhou 213016, China
| | - Yi Zhao
- China
Petroleum & Chemical Corporation Northwest Oilfield Branch, Petroleum Engineering Technology Research Institute, Urumqi 830011, China
| | - Yang Liu
- Jiangsu
Key Laboratory of Oil and Gas Storage & Transportation Technology, Changzhou University, Changzhou 213016, China
| | - Jiawen Xu
- Jiangsu
Key Laboratory of Oil and Gas Storage & Transportation Technology, Changzhou University, Changzhou 213016, China
| | - Qianli Ma
- Jiangsu
Key Laboratory of Oil and Gas Storage & Transportation Technology, Changzhou University, Changzhou 213016, China
| | - Shangfei Song
- National
Engineering Laboratory for Pipeline Safety/ MOE Key Laboratory of
Petroleum Engineering/ Beijing Key Laboratory of Urban Oil and Gas
Distribution Technology, China University
of Petroleum-Beijing, Beijing 102249, China
| | - Shidong Zhou
- Jiangsu
Key Laboratory of Oil and Gas Storage & Transportation Technology, Changzhou University, Changzhou 213016, China
| |
Collapse
|
16
|
Mileo PGM, Rogge SMJ, Houlleberghs M, Breynaert E, Martens JA, Van Speybroeck V. Interfacial study of clathrates confined in reversed silica pores. JOURNAL OF MATERIALS CHEMISTRY. A 2021; 9:21835-21844. [PMID: 34707871 PMCID: PMC8491980 DOI: 10.1039/d1ta03105h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 08/22/2021] [Indexed: 05/08/2023]
Abstract
Storing methane in clathrates is one of the most promising alternatives for transporting natural gas (NG) as it offers similar gas densities to liquefied and compressed NG while offering lower safety risks. However, the practical use of clathrates is limited given the extremely low temperatures and high pressures necessary to form these structures. Therefore, it has been suggested to confine clathrates in nanoporous materials, as this can facilitate clathrate's formation conditions while preserving its CH4 volumetric storage. Yet, the choice of nanoporous materials to be employed as the clathrate growing platform is still rather arbitrary. Herein, we tackle this challenge in a systematic way by computationally exploring the stability of clathrates confined in alkyl-grafted silica materials with different pore sizes, ligand densities and ligand types. Based on our findings, we are able to propose key design criteria for nanoporous materials favoring the stability of a neighbouring clathrate phase, namely large pore sizes, high ligand densities, and smooth pore walls. We hope that the atomistic insight provided in this work will guide and facilitate the development of new nanomaterials designed to promote the formation of clathrates.
Collapse
Affiliation(s)
- Paulo G M Mileo
- Center for Molecular Modeling (CMM), Ghent University Technologiepark 46 B-9052 Zwijnaarde Belgium
| | - Sven M J Rogge
- Center for Molecular Modeling (CMM), Ghent University Technologiepark 46 B-9052 Zwijnaarde Belgium
| | - Maarten Houlleberghs
- Center for Surface Chemistry and Catalysis, Katholieke Universiteit Leuven Celestijnenlaan 200F 3001 Heverlee Belgium
| | - Eric Breynaert
- Center for Surface Chemistry and Catalysis, Katholieke Universiteit Leuven Celestijnenlaan 200F 3001 Heverlee Belgium
| | - Johan A Martens
- Center for Surface Chemistry and Catalysis, Katholieke Universiteit Leuven Celestijnenlaan 200F 3001 Heverlee Belgium
| | - Veronique Van Speybroeck
- Center for Molecular Modeling (CMM), Ghent University Technologiepark 46 B-9052 Zwijnaarde Belgium
| |
Collapse
|
17
|
Wang L, Lu X, Xu Y. Experiment Investigation of SiO 2 Containing Amino Groups as a Kinetic Promoter for CO 2 Hydrates. ACS OMEGA 2021; 6:19748-19756. [PMID: 34368562 PMCID: PMC8340390 DOI: 10.1021/acsomega.1c02440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Accepted: 07/14/2021] [Indexed: 06/13/2023]
Abstract
To diminish the greenhouse effect by reducing CO2 emission into the air based on a capture and sequestration method through hydrates, the thermodynamic and kinetic effects of additives on CO2 hydrate formation under 1.5 MPa in the presence of 5, 6, 8, 10, and 20 wt % RNS-A (reactive SiO2 containing amino groups) were studied, and the stirrer speed was set to 800 rpm. This paper calculated the gas consumption and explained the possible mechanisms of RNS-A on CO2 hydrates. The results showed that RNS-A was a kinetic additive instead of a thermodynamic one. It was found that 5-10 wt % RNS-A all shortened the induction time of hydrates, but only 5 and 6 wt % RNS-A increased the gas consumption of CO2 hydrates. Although we observed the shortest induction time at a 10 wt % RNS-A system, the lowest gas consumption indicated its weak CO2 capture and storage ability. In addition, when the concentration was 6 wt %, RNS-A had the highest gas consumption and its reaction time was relatively short. Considering the induction time and gas consumption, 6 wt % RNS-A was the optimal RNS-A concentration for CO2 capture and sequestration, which was the most suitable for practical applications.
Collapse
Affiliation(s)
- Lanyun Wang
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
- Collaborative
Innovation Center for Coal Safety Production & High-Efficient-Clean
Utilization for Coal by Provincial and Ministerial Co-construction, Jiaozuo 454003, China
- State
Key Laboratory Cultivation Base for Gas Geology and Gas Control in
Henan Polytechnic University, Jiaozuo 454003, China
| | - Xiaoran Lu
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
| | - Yongliang Xu
- School
of Safety Science and Engineering, Henan
Polytechnic University, Jiaozuo 454003, China
- Collaborative
Innovation Center for Coal Safety Production & High-Efficient-Clean
Utilization for Coal by Provincial and Ministerial Co-construction, Jiaozuo 454003, China
- State
Key Laboratory Cultivation Base for Gas Geology and Gas Control in
Henan Polytechnic University, Jiaozuo 454003, China
| |
Collapse
|
18
|
Liu N, Zhu H, Zhou J, Yang L, Liu D. Molecular dynamics simulations on formation of CO2 hydrate in the presence of metal particles. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115793] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
19
|
Arjun A, Bolhuis PG. Molecular Understanding of Homogeneous Nucleation of CO 2 Hydrates Using Transition Path Sampling. J Phys Chem B 2021; 125:338-349. [PMID: 33379869 PMCID: PMC7816195 DOI: 10.1021/acs.jpcb.0c09915] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Revised: 12/11/2020] [Indexed: 11/29/2022]
Abstract
Carbon dioxide hydrate is a solid built from hydrogen-bond stabilized water cages that encapsulate individual CO2 molecules. As potential candidates for reducing greenhouse gases, hydrates have attracted attention from both the industry and scientific community. Under high pressure and low temperature, hydrates are formed spontaneously from a mixture of CO2 and water via nucleation and growth. Yet, for moderate undercooling, i.e., moderate supersaturation, studying hydrate formation with molecular simulations is very challenging due to the high nucleation barriers involved. We investigate the homogeneous nucleation mechanism of CO2 hydrate as a function of temperature using transition path sampling (TPS), which generates ensembles of unbiased dynamical trajectories across the high barrier between the liquid and solid states. The resulting path ensembles reveal that at high driving force (low temperature), amorphous structures are predominantly formed, with 4151062 cages being the most abundant. With increasing temperature, the nucleation mechanism changes, and 51262 becomes the most abundant cage type, giving rise to the crystalline sI structure. Reaction coordinate analysis can reveal the most important collective variable involved in the mechanism. With increasing temperature, we observe a shift from a single feature (size of the nucleus) to a 2-dimensional (size and cage type) variable as the salient ingredient of the reaction coordinate, and then back to only the nucleus size. This finding is in line with the underlying shift from an amorphous to a crystalline nucleation channel. Modeling such complex phase transformations using transition path sampling gives unbiased insight into the molecular mechanisms toward different polymorphs, and how these are determined by thermodynamics and kinetics. This study will be beneficial for researchers aiming to produce such hydrates with different polymorphic forms.
Collapse
Affiliation(s)
- A. Arjun
- van ’t Hoff Institute
for Molecular Sciences, University of Amsterdam, PO Box 94157, 1090 GD Amsterdam, The Netherlands
| | - P. G. Bolhuis
- van ’t Hoff Institute
for Molecular Sciences, University of Amsterdam, PO Box 94157, 1090 GD Amsterdam, The Netherlands
| |
Collapse
|
20
|
Denning S, Majid AA, Lucero JM, Crawford JM, Carreon MA, Koh CA. Metal-Organic Framework HKUST-1 Promotes Methane Hydrate Formation for Improved Gas Storage Capacity. ACS APPLIED MATERIALS & INTERFACES 2020; 12:53510-53518. [PMID: 33186007 DOI: 10.1021/acsami.0c15675] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The large demand of natural gas consumption requires an effective technology to purify and store methane, the main component of natural gas. Metal-organic frameworks and gas hydrates are highly appealing materials for the efficient storage of industrially relevant gases, including methane. In this study, the methane storage capacity of the combination of methane hydrates and HKUST-1, a copper-based metal-organic framework, was studied using high pressure differential scanning calorimetry. The results show a synergistic effect, as the addition of HKUST-1 promoted hydrate growth, thus increasing the amount of water converted to hydrate from 5.9 to 87.2% and the amount of methane stored, relative to the amount of water present, from 0.55 to 8.1 mmol/g. The success of HKUST-1 as a promoter stems mainly from its large surface area, high thermal conductivity, and hydrophilicity. These distinctive properties led to a kinetically favorable decrease in hydrate growth induction period by 4.4 h upon the addition of HKUST-1. Powder X-ray diffraction and nitrogen isotherm suggests that the hydrate formation occurs primarily on the surface of HKUST-1 rather than within the pores. Remarkably, the HKUST-1 crystals show no significant changes in terms of structural integrity after many cycles of hydrate formation and dissociation, which results in the material having a long life cycle. These results confirm the beneficial role of HKUST-1 as a promoter for gas hydrate formation to increase methane gas storage capacity.
Collapse
Affiliation(s)
- Shurraya Denning
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Ahmad Aa Majid
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Jolie M Lucero
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, United States
| | - James M Crawford
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Moises A Carreon
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, United States
| | - Carolyn A Koh
- Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, United States
| |
Collapse
|
21
|
Sargeant E, Kolodziej A, Le Duff CS, Rodriguez P. Electrochemical Conversion of CO 2 and CH 4 at Subzero Temperatures. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01676] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Elizabeth Sargeant
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Adam Kolodziej
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Cécile S. Le Duff
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Paramaconi Rodriguez
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| |
Collapse
|
22
|
Prasad PSR, Kiran BS, Sowjanya K. Enhanced methane gas storage in the form of hydrates: role of the confined water molecules in silica powders. RSC Adv 2020; 10:17795-17804. [PMID: 35515598 PMCID: PMC9053743 DOI: 10.1039/d0ra01754j] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 04/29/2020] [Indexed: 12/19/2022] Open
Abstract
Methane hydrates are promising materials for storage and transportation of natural gas; however, the slow kinetics and inefficient water to hydrate conversions impede its broad scale utilisation. The purpose of the present study is to demonstrate rapid (2-3 h) and efficient methane hydrate conversions by utilising the water molecules confined in the intra- and inter-granular space of silica powders. All the experiments were conducted with amorphous silica (10 g) powders of 2-30 μm; 10-20 nm grain size, to mimic the hydrate formations in fine sand and clay dominated environments under moderate methane pressure (7-8 MPa). Encasing of methane molecules in hydrate cages was confirmed by Raman spectroscopic (ex situ) and thermodynamic phase boundary measurements. The present studies reveal that the water to hydrate conversion is relatively slower in 10-20 nm grain size silica, although the nucleation event is rapid in both silicas. The process of hydrate conversion is vastly diffusion-controlled, and this was distinctly observed during the hydrate growth in nanosize silica.
Collapse
Affiliation(s)
- Pinnelli S R Prasad
- Gas Hydrate Division, CSIR-National Geophysical Research Institute (CSIR-NGRI) Hyderabad - 500 007 India +91 40 2717 1564 +91 40 2701 2710
| | - Burla Sai Kiran
- Gas Hydrate Division, CSIR-National Geophysical Research Institute (CSIR-NGRI) Hyderabad - 500 007 India +91 40 2717 1564 +91 40 2701 2710.,Academy of Scientific and Innovative Research (AcSIR), CSIR-NGRI Campus Hyderabad - 500 007 India
| | - Kandadai Sowjanya
- Gas Hydrate Division, CSIR-National Geophysical Research Institute (CSIR-NGRI) Hyderabad - 500 007 India +91 40 2717 1564 +91 40 2701 2710
| |
Collapse
|
23
|
Mirzaeifard S, Servio P, Rey AD. Characterization of nucleation of methane hydrate crystals: Interfacial theory and molecular simulation. J Colloid Interface Sci 2019; 557:556-567. [DOI: 10.1016/j.jcis.2019.09.056] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/06/2019] [Accepted: 09/17/2019] [Indexed: 01/18/2023]
|
24
|
Mirzaeifard S, Servio P, Rey AD. Molecular dynamics characterization of the water-methane, ethane, and propane gas mixture interfaces. Chem Eng Sci 2019. [DOI: 10.1016/j.ces.2019.01.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
25
|
Touil A, Broseta D, Desmedt A. Gas Hydrate Crystallization in Thin Glass Capillaries: Roles of Supercooling and Wettability. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:12569-12581. [PMID: 31419142 DOI: 10.1021/acs.langmuir.9b01146] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We designed and implemented an experimental methodology to investigate gas hydrate formation and growth around a water-guest meniscus in a thin glass capillary, thus mimicking pore-scale processes in sediments. The glass capillary acts as a high-pressure optical cell in a range of supercooling conditions from 0.1 °C, i.e., very close to hydrate dissociation conditions, to ∼35 °C, very near the metastability limit. Liquid or gaseous CO2 is the guest phase in most of the experiments reported in this paper, and N2 in a few of them. The setup affords detailed microscopic observation of the roles of the key parameters on hydrate growth and interaction with the substrate: supercooling and substrate wettability. At low supercooling (less than 0.5 °C), a novel hydrate growth process is discovered, which consists of a hollow crystal originating from the meniscus and advancing on the guest side along the glass, fed by a thick water layer sandwiched between the glass and this crystal.
Collapse
Affiliation(s)
- Abdelhafid Touil
- Laboratoire des Fluides Complexes et de leurs Réservoirs (LFCR), UMR 5150 , Centre National de la Recherche Scientifique (CNRS)/TOTAL/Energy Environment Solutions, Université de Pau et des Pays de l'Adour (E2S UPPA) , 64000 Pau , France
- Direction Centrale de Recherche et Développement , Sonatrach , 35000 Boumerdès , Algeria
| | - Daniel Broseta
- Laboratoire des Fluides Complexes et de leurs Réservoirs (LFCR), UMR 5150 , Centre National de la Recherche Scientifique (CNRS)/TOTAL/Energy Environment Solutions, Université de Pau et des Pays de l'Adour (E2S UPPA) , 64000 Pau , France
| | - Arnaud Desmedt
- Institut des Sciences Moléculaires (ISM), UMR 5255 , Centre National de la Recherche Scientifique (CNRS), Université de Bordeaux , 33405 Talence , France
| |
Collapse
|
26
|
Fundamental Investigation of the Effects of Modified Starch, Carboxymethylcellulose Sodium, and Xanthan Gum on Hydrate Formation under Different Driving Forces. ENERGIES 2019. [DOI: 10.3390/en12102026] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The development of a new drilling fluid system with hydrate inhibition is of great significance for drilling safety in gas hydrate-bearing sediments. Considering the importance of the selection of a suitable thickener for drilling fluid systems under weak and strong driving forces, the hydrate inhibition of 0.1–0.5 wt% modified starch (MS), carboxymethylcellulose sodium (CMC), and xanthan gum (XG) aqueous solutions was studied. The applicability of these three thickeners were investigated through hydrate formation experiments, mesostructure observations, water activity tests, bubble retention observations, and rheological property tests. The results show that (1) under weak driving force, 0.3 wt% or higher concentration CMC and 0.3 wt% XG can almost completely inhibit hydrate formation due to the interactions between relatively small amounts of free water and CH4 molecules. Furthermore, the hydrate inhibition of higher XG concentrations was decreased due to their strong foam stability, leading to good contact between free water and CH4 molecules. Meanwhile, the hydrate inhibition of MS was weaker when compared with that of CMC and XG at the same concentrations. (2) Under strong driving force, the existence of the three 0.1–0.5 wt% thickeners could only slow down the hydrate formation rate, and hydrate inhibition due to XG was slightly better than that of the other two. This result implies that the effects of the different mesostructures on hydrate formation were severely weakened. Finally, (3) the tackifying effect of CMC was found to be stronger than that of XG and MS, and the rheological properties of the CMC solution were shown to be relatively weak compared to those of the XG and MS solutions; the CMC solution showed a more significant increase in viscosity with decreasing temperature, which is related to the differences in the mesostructures. Therefore, when the driving force of hydrate formation is relatively low, CMC is a good choice for the drilling fluid system when there is no requirement for cooling, while XG is more applicable for a system that needs cooling. In the case of a stronger driving force, XG is the optimal choice irrespective of whether the drilling fluid system needs cooling or not.
Collapse
|
27
|
Hou J, Bai D, Zhou W. Methane Hydrate Nucleation within Elastic Confined Spaces: Suitable Spacing and Elasticity Can Accelerate the Nucleation. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:10889-10896. [PMID: 30157653 DOI: 10.1021/acs.langmuir.8b02387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Elastic materials are candidates for process intensification of gas storage by forming gas hydrate. In this work, molecular dynamics simulations of hydrate nucleation in elastic silica double layers were performed to study the effect of elastic confined spaces on hydrate formation. It is found that in narrow confined spaces, hexagonal rings dominated the hydrogen bond network of water molecules established rapidly by a multisite nucleation mechanism. With molecules added, a bilayer water structure was formed finally because elastic space can adapt the volume expansion. In medium and wide confined spaces, hydrates were formed from a series of "pseudo cages" which are considered as precursors of complete hydrate cages. Moreover, the induction time for nucleation was a minimum when the elasticity of the silica layer changes: nucleation is fastest in the weak-elastic system. When the elasticity increases, it becomes hard to adapt the volume expansion during nucleation and also difficult to nucleate in very weak-elastic systems because of the fluctuation of the layers.
Collapse
Affiliation(s)
- Jingpeng Hou
- Department of Chemistry, School of Science/Key Laboratory of Cosmetic, China National Light Industry , Beijing Technology and Business University , Beijing 100048 , PR China
| | - Dongsheng Bai
- Department of Chemistry, School of Science/Key Laboratory of Cosmetic, China National Light Industry , Beijing Technology and Business University , Beijing 100048 , PR China
| | - Wei Zhou
- Department of Chemistry, School of Science/Key Laboratory of Cosmetic, China National Light Industry , Beijing Technology and Business University , Beijing 100048 , PR China
| |
Collapse
|
28
|
Warrier P, Khan MN, Srivastava V, Maupin CM, Koh CA. Overview: Nucleation of clathrate hydrates. J Chem Phys 2018; 145:211705. [PMID: 28799342 DOI: 10.1063/1.4968590] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Molecular level knowledge of nucleation and growth of clathrate hydrates is of importance for advancing fundamental understanding on the nature of water and hydrophobic hydrate formers, and their interactions that result in the formation of ice-like solids at temperatures higher than the ice-point. The stochastic nature and the inability to probe the small length and time scales associated with the nucleation process make it very difficult to experimentally determine the molecular level changes that lead to the nucleation event. Conversely, for this reason, there have been increasing efforts to obtain this information using molecular simulations. Accurate knowledge of how and when hydrate structures nucleate will be tremendously beneficial for the development of sustainable hydrate management strategies in oil and gas flowlines, as well as for their application in energy storage and recovery, gas separation, carbon sequestration, seawater desalination, and refrigeration. This article reviews various aspects of hydrate nucleation. First, properties of supercooled water and ice nucleation are reviewed briefly due to their apparent similarity to hydrates. Hydrate nucleation is then reviewed starting from macroscopic observations as obtained from experiments in laboratories and operations in industries, followed by various hydrate nucleation hypotheses and hydrate nucleation driving force calculations based on the classical nucleation theory. Finally, molecular simulations on hydrate nucleation are discussed in detail followed by potential future research directions.
Collapse
Affiliation(s)
- Pramod Warrier
- Center for Hydrate Research, Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, USA
| | - M Naveed Khan
- Center for Hydrate Research, Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, USA
| | - Vishal Srivastava
- Center for Hydrate Research, Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, USA
| | - C Mark Maupin
- Center for Hydrate Research, Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, USA
| | - Carolyn A Koh
- Center for Hydrate Research, Chemical and Biological Engineering Department, Colorado School of Mines, Golden, Colorado 80401, USA
| |
Collapse
|
29
|
Cox SJ, Taylor DJF, Youngs TGA, Soper AK, Totton TS, Chapman RG, Arjmandi M, Hodges MG, Skipper NT, Michaelides A. Formation of Methane Hydrate in the Presence of Natural and Synthetic Nanoparticles. J Am Chem Soc 2018; 140:3277-3284. [PMID: 29401390 PMCID: PMC5860788 DOI: 10.1021/jacs.7b12050] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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.
Collapse
Affiliation(s)
- Stephen J Cox
- Department of Chemistry , University College London , 20 Gordon Street , London WC1H 0AJ , United Kingdom.,Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom
| | - Diana J F Taylor
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom.,Department of Physics and Astronomy , University College London , Gower Street , London WC1E 6BT , United Kingdom
| | - Tristan G A Youngs
- ISIS Facility , STFC Rutherford Appleton Laboratory , Harwell Oxford , Didcot OX11 0QX , United Kingdom
| | - Alan K Soper
- ISIS Facility , STFC Rutherford Appleton Laboratory , Harwell Oxford , Didcot OX11 0QX , United Kingdom
| | - Tim S Totton
- BP Exploration Operating Co. Ltd , Chertsey Road , Sunbury-on-Thames TW16 7LN , United Kingdom
| | - Richard G Chapman
- BP Exploration Operating Co. Ltd , Chertsey Road , Sunbury-on-Thames TW16 7LN , United Kingdom
| | - Mosayyeb Arjmandi
- BP Exploration Operating Co. Ltd , Chertsey Road , Sunbury-on-Thames TW16 7LN , United Kingdom
| | - Michael G Hodges
- BP Exploration Operating Co. Ltd , Chertsey Road , Sunbury-on-Thames TW16 7LN , United Kingdom
| | - Neal T Skipper
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom.,Department of Physics and Astronomy , University College London , Gower Street , London WC1E 6BT , United Kingdom
| | - Angelos Michaelides
- Thomas Young Centre and London Centre for Nanotechnology , 17-19 Gordon Street , London WC1H 0AH , United Kingdom.,Department of Physics and Astronomy , University College London , Gower Street , London WC1E 6BT , United Kingdom
| |
Collapse
|
30
|
DeFever RS, Sarupria S. Nucleation mechanism of clathrate hydrates of water-soluble guest molecules. J Chem Phys 2017; 147:204503. [DOI: 10.1063/1.4996132] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ryan S. DeFever
- Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, USA
| | - Sapna Sarupria
- Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, South Carolina 29634, USA
| |
Collapse
|
31
|
He Z, Linga P, Jiang J. CH 4 Hydrate Formation between Silica and Graphite Surfaces: Insights from Microsecond Molecular Dynamics Simulations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:11956-11967. [PMID: 28991480 DOI: 10.1021/acs.langmuir.7b02711] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Microsecond simulations have been performed to investigate CH4 hydrate formation from gas/water two-phase systems between silica and graphite surfaces, respectively. The hydrophilic silica and hydrophobic graphite surfaces exhibit substantially different effects on CH4 hydrate formation. The graphite surface adsorbs CH4 molecules to form a nanobubble with a flat or negative curvature, resulting in a low aqueous CH4 concentration, and hydrate nucleation does not occur during 2.5 μs simulation. Moreover, an ordered interfacial water bilayer forms between the nanobubble and graphite surface thus preventing their direct contact. In contrast, the hydroxylated-silica surface prefers to be hydrated by water, with a cylindrical nanobubble formed in the solution, leading to a high aqueous CH4 concentration and hydrate nucleation in the bulk region; during hydrate growth, the nanobubble is gradually covered by hydrate solid and separated from the water phase, hence slowing growth. The silanol groups on the silica surface can form strong hydrogen bonds with water, and hydrate cages need to match the arrangements of silanols to form more hydrogen bonds. At the end of the simulation, the hydrate solid is separated from the silica surface by liquid water, with only several cages forming hydrogen bonds with the silica surface, mainly due to the low CH4 aqueous concentrations near the surface. To further explore hydrate formation between graphite surfaces, CH4/water homogeneous solution systems are also simulated. CH4 molecules in the solution are adsorbed onto graphite and hydrate nucleation occurs in the bulk region. During hydrate growth, the adsorbed CH4 molecules are gradually converted into hydrate solid. It is found that the hydrate-like ordering of interfacial water induced by graphite promotes the contact between hydrate solid and graphite. We reveal that the ability of silanol groups on silica to form strong hydrogen bonds to stabilize incipient hydrate solid, as well as the ability of graphite to adsorb CH4 molecules and induce hydrate-like ordering of the interfacial water, are the key factors to affect CH4 hydrate formation between silica and graphite surfaces.
Collapse
Affiliation(s)
- Zhongjin He
- Department of Chemical and Biomolecular Engineering, National University of Singapore , Singapore 117576, Singapore
| | - Praveen Linga
- Department of Chemical and Biomolecular Engineering, National University of Singapore , Singapore 117576, Singapore
| | - Jianwen Jiang
- Department of Chemical and Biomolecular Engineering, National University of Singapore , Singapore 117576, Singapore
| |
Collapse
|
32
|
Touil A, Broseta D, Hobeika N, Brown R. Roles of Wettability and Supercooling in the Spreading of Cyclopentane Hydrate over a Substrate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:10965-10977. [PMID: 28910532 DOI: 10.1021/acs.langmuir.7b02121] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We use transmission optical microscopy to observe cyclopentane hydrate growth in sub-mm, open glass capillaries, mimicking cylindrical pores. The capillary is initially loaded with water and the guest fluid (cyclopentane) and thus possesses three menisci, that between water and cyclopentane (CP) in the middle and two menisci with the vapors at the ends. At temperatures T below the equilibrium temperature Teq ≈ 7 °C, the hydrate nucleates on the water-CP meniscus, rapidly coating it with an immobile, polycrystalline crust. Continued movement of the other two menisci provides insights into hydrate growth mechanisms, via the consumption and displacement of the fluids. On water-wet glass, the subsequent growth consists of a hydrate "halo" creeping with an underlying water layer on the glass on the CP side of the meniscus. Symmetrically, on CP-wet glass (silane-treated), a halo and a CP layer grow on the water side of the interface. No halo is observed on intermediate wet glass. The halo consists of an array of large monocrystals, over a thick water layer at low supercooling (ΔT = Teq - T below 5 K), and a finer, polycrystalline texture over a thinner water layer at higher ΔT. Furthermore, the velocity varies as ΔTα, with α ≈ 2.7, making the early stages of growth very similar to gas hydrate crusts growing over water-guest interfaces. Beyond a length in the millimeter range, the halo and its water layer abruptly decelerate and thin down to submicron thickness. The halo passes through the meniscus with the vapor without slowing down or change of texture. A model of the mass balance of the fluids helps rationalize all of these observations.
Collapse
Affiliation(s)
- Abdelhafid Touil
- Laboratoire des fluides complexes et de leurs réservoirs (LFCR), UMR CNRS 5150, Université de Pau et des Pays de l'Adour , Av. de l'Université, B.P. 1155, 64013 Pau Cedex, France
| | - Daniel Broseta
- Laboratoire des fluides complexes et de leurs réservoirs (LFCR), UMR CNRS 5150, Université de Pau et des Pays de l'Adour , Av. de l'Université, B.P. 1155, 64013 Pau Cedex, France
| | - Nelly Hobeika
- Laboratoire des fluides complexes et de leurs réservoirs (LFCR), UMR CNRS 5150, Université de Pau et des Pays de l'Adour , Av. de l'Université, B.P. 1155, 64013 Pau Cedex, France
| | - Ross Brown
- Institut des sciences analytiques et de physico-chimie pour l'environnement et les matériaux (IPREM), UMR CNRS 5254, Université de Pau et des Pays de l'Adour , Hélioparc, 2, Av. P. Angot, 64053 Pau Cedex, France
| |
Collapse
|
33
|
Elasticity and Stability of Clathrate Hydrate: Role of Guest Molecule Motions. Sci Rep 2017; 7:1290. [PMID: 28465527 PMCID: PMC5431056 DOI: 10.1038/s41598-017-01369-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Accepted: 03/29/2017] [Indexed: 12/02/2022] Open
Abstract
Molecular dynamic simulations were performed to determine the elastic constants of carbon dioxide (CO2) and methane (CH4) hydrates at one hundred pressure–temperature data points, respectively. The conditions represent marine sediments and permafrost zones where gas hydrates occur. The shear modulus and Young’s modulus of the CO2 hydrate increase anomalously with increasing temperature, whereas those of the CH4 hydrate decrease regularly with increase in temperature. We ascribe this anomaly to the kinetic behavior of the linear CO2 molecule, especially those in the small cages. The cavity space of the cage limits free rotational motion of the CO2 molecule at low temperature. With increase in temperature, the CO2 molecule can rotate easily, and enhance the stability and rigidity of the CO2 hydrate. Our work provides a key database for the elastic properties of gas hydrates, and molecular insights into stability changes of CO2 hydrate from high temperature of ~5 °C to low decomposition temperature of ~−150 °C.
Collapse
|
34
|
Zhang Z, Guo GJ. The effects of ice on methane hydrate nucleation: a microcanonical molecular dynamics study. Phys Chem Chem Phys 2017; 19:19496-19505. [DOI: 10.1039/c7cp03649c] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The NVE simulations realize the ice shrinking when methane hydrate nucleates both heterogeneously and homogeneously.
Collapse
Affiliation(s)
- Zhengcai Zhang
- Key Laboratory of Earth and Planetary Physics
- Institute of Geology and Geophysics
- Chinese Academy of Sciences
- Beijing 100029
- China
| | - Guang-Jun Guo
- Key Laboratory of Earth and Planetary Physics
- Institute of Geology and Geophysics
- Chinese Academy of Sciences
- Beijing 100029
- China
| |
Collapse
|
35
|
Li Y, Zhang D, Bai D, Li S, Wang X, Zhou W. Size Effect of Silica Shell on Gas Uptake Kinetics in Dry Water. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:7365-71. [PMID: 27350177 DOI: 10.1021/acs.langmuir.6b01918] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Two kinds of dry water (DW) particles are prepared by mixing water and hydrophobic silica particles with nanometer or micrometer dimensions, and the two DW particles are found to have similar size distributions regardless of the size of the silica shell. The CO2 uptake kinetics of DW with nanometer (nanoshell) and micrometer shells (microshell) are measured, and both uptake rate and capacity show the obvious size effect of the silica shell. The DW with a microshell possesses a larger uptake capacity, whereas the DW with a nanoshell has a faster uptake rate. By comparing the uptake kinetics of soluble NH3 and CO2 further, we found that the microshell enhances the stability and the dispersion degree of DW and the nanoshell offers a shorter path for the transit of guest gas into the water core. Furthermore, molecular dynamics simulation is introduced to illustrate the nanosize effect of the silica shell on the initial step of the gas uptake. It is found that the concentration of gas molecules close to the silica shell is higher than that in the bulk water core. With the increase in the size of the silica shell, the amount of CO2 in the silica shell decreases, and it is easier for the gas uptake to reach steady state.
Collapse
Affiliation(s)
- Yong Li
- Department of Chemistry, School of Science, Beijing Technology and Business University , Beijing 100048, China
| | - Diwei Zhang
- Department of Chemistry, School of Science, Beijing Technology and Business University , Beijing 100048, China
| | - Dongsheng Bai
- Department of Chemistry, School of Science, Beijing Technology and Business University , Beijing 100048, China
| | - Shujing Li
- Department of Chemistry, School of Science, Beijing Technology and Business University , Beijing 100048, China
| | - Xinrui Wang
- Department of Chemistry, School of Science, Beijing Technology and Business University , Beijing 100048, China
| | - Wei Zhou
- Department of Chemistry, School of Science, Beijing Technology and Business University , Beijing 100048, China
| |
Collapse
|
36
|
Sosso G, Chen J, Cox SJ, Fitzner M, Pedevilla P, Zen A, Michaelides A. Crystal Nucleation in Liquids: Open Questions and Future Challenges in Molecular Dynamics Simulations. Chem Rev 2016; 116:7078-116. [PMID: 27228560 PMCID: PMC4919765 DOI: 10.1021/acs.chemrev.5b00744] [Citation(s) in RCA: 378] [Impact Index Per Article: 47.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Indexed: 11/28/2022]
Abstract
The nucleation of crystals in liquids is one of nature's most ubiquitous phenomena, playing an important role in areas such as climate change and the production of drugs. As the early stages of nucleation involve exceedingly small time and length scales, atomistic computer simulations can provide unique insights into the microscopic aspects of crystallization. In this review, we take stock of the numerous molecular dynamics simulations that, in the past few decades, have unraveled crucial aspects of crystal nucleation in liquids. We put into context the theoretical framework of classical nucleation theory and the state-of-the-art computational methods by reviewing simulations of such processes as ice nucleation and the crystallization of molecules in solutions. We shall see that molecular dynamics simulations have provided key insights into diverse nucleation scenarios, ranging from colloidal particles to natural gas hydrates, and that, as a result, the general applicability of classical nucleation theory has been repeatedly called into question. We have attempted to identify the most pressing open questions in the field. We believe that, by improving (i) existing interatomic potentials and (ii) currently available enhanced sampling methods, the community can move toward accurate investigations of realistic systems of practical interest, thus bringing simulations a step closer to experiments.
Collapse
Affiliation(s)
- Gabriele
C. Sosso
- Thomas Young Centre, London
Centre for Nanotechnology and Department of Physics and Astronomy, University College London, Gower Street WC1E
6BT London, U.K.
| | - Ji Chen
- Thomas Young Centre, London
Centre for Nanotechnology and Department of Physics and Astronomy, University College London, Gower Street WC1E
6BT London, U.K.
| | | | - Martin Fitzner
- Thomas Young Centre, London
Centre for Nanotechnology and Department of Physics and Astronomy, University College London, Gower Street WC1E
6BT London, U.K.
| | - Philipp Pedevilla
- Thomas Young Centre, London
Centre for Nanotechnology and Department of Physics and Astronomy, University College London, Gower Street WC1E
6BT London, U.K.
| | - Andrea Zen
- Thomas Young Centre, London
Centre for Nanotechnology and Department of Physics and Astronomy, University College London, Gower Street WC1E
6BT London, U.K.
| | - Angelos Michaelides
- Thomas Young Centre, London
Centre for Nanotechnology and Department of Physics and Astronomy, University College London, Gower Street WC1E
6BT London, U.K.
| |
Collapse
|
37
|
Microscopic Origin of Strain Hardening in Methane Hydrate. Sci Rep 2016; 6:23548. [PMID: 27009239 PMCID: PMC4806379 DOI: 10.1038/srep23548] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Accepted: 03/09/2016] [Indexed: 12/11/2022] Open
Abstract
It has been reported for a long time that methane hydrate presents strain hardening, whereas the strength of normal ice weakens with increasing strain after an ultimate strength. However, the microscopic origin of these differences is not known. Here, we investigated the mechanical characteristics of methane hydrate and normal ice by compressive deformation test using molecular dynamics simulations. It is shown that methane hydrate exhibits strain hardening only if the hydrate is confined to a certain finite cross-sectional area that is normal to the compression direction. For normal ice, it does not present strain hardening under the same conditions. We show that hydrate guest methane molecules exhibit no long-distance diffusion when confined to a finite-size area. They appear to serve as non-deformable units that prevent hydrate structure failure, and thus are responsible for the strain-hardening phenomenon.
Collapse
|
38
|
Li H, Stanwix P, Aman Z, Johns M, May E, Wang L. Raman Spectroscopic Studies of Clathrate Hydrate Formation in the Presence of Hydrophobized Particles. J Phys Chem A 2016; 120:417-24. [DOI: 10.1021/acs.jpca.5b11247] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Huijuan Li
- School
of Chemical Engineering, The University of Queensland, Brisbane, Australia
| | - Paul Stanwix
- School
of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
| | - Zachary Aman
- School
of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
| | - Michael Johns
- School
of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
| | - Eric May
- School
of Mechanical and Chemical Engineering, The University of Western Australia, Perth, Australia
| | - Liguang Wang
- School
of Chemical Engineering, The University of Queensland, Brisbane, Australia
| |
Collapse
|