Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular Simulation

In situ gas content is an important parameter associating coalbed methane, while the influence of pressure and temperature on methane adsorption and desorption still needs to be revealed. In this study, the molecular structure and methane adsorption capacity of anthracite coal collected from Diandon...

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Main Authors: Tieya Jing, Jian Zhang, Mingyu Zhu, Wentao Zhao, Juan Zhou, Yulong Yin
Format: Article
Language:English
Published: Wiley 2023-01-01
Series:Geofluids
Online Access:http://dx.doi.org/10.1155/2023/8528359
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author Tieya Jing
Jian Zhang
Mingyu Zhu
Wentao Zhao
Juan Zhou
Yulong Yin
author_facet Tieya Jing
Jian Zhang
Mingyu Zhu
Wentao Zhao
Juan Zhou
Yulong Yin
author_sort Tieya Jing
collection DOAJ
description In situ gas content is an important parameter associating coalbed methane, while the influence of pressure and temperature on methane adsorption and desorption still needs to be revealed. In this study, the molecular structure and methane adsorption capacity of anthracite coal collected from Diandong Coalfield (China) were studied based on 13C nuclear magnetic resonance (13C NMR), Fourier transform infrared spectroscopy (FT-IR), and methane isothermal adsorption experiment. The results show that the carbon skeleton of coal sample is mainly composed by aromatic carbon (72%), followed by aliphatic carbon structure (14.2%). Carbons connected to the oxygen atoms contribute 13.7% of the total carbons in coal molecule, and the oxygen atoms are mainly in the form of carbonyl. The 2-dimension structure and 3-dimension molecular structure of coal sample was also reconstructed. The average chemical formula of the coal molecule is C200H133O21N3. The experimental methane adsorption isothermal data of the coal sample under different temperatures shows that with increasing the temperature, the methane adsorption amount at each pressure decreases obviously. At 7 MPa and 20°C, the methane adsorption amount of the coal sample is 28.5 cm3/g. Comparably, at 100°C and 7 MPa, the methane adsorption amount is only 15.9 cm3/g, decreasing by 44%. In mesopores, temperature has stronger influence on methane adsorption under higher pressure than that of lower pressure. On the contrary, in micropores, temperature has weaker effects on methane adsorption at higher pressure than that at lower pressure. The results can be beneficial for understanding methane adsorption characteristics of deep coal.
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institution Kabale University
issn 1468-8123
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spelling doaj-art-ef36f0000f7f4567a634c948bd3909752025-02-03T05:44:21ZengWileyGeofluids1468-81232023-01-01202310.1155/2023/8528359Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular SimulationTieya Jing0Jian Zhang1Mingyu Zhu2Wentao Zhao3Juan Zhou4Yulong Yin5Beijing Key Laboratory of CO2 Capture and TreatmentBeijing Key Laboratory of CO2 Capture and TreatmentBeijing Key Laboratory of CO2 Capture and TreatmentBeijing Key Laboratory of CO2 Capture and TreatmentBeijing Key Laboratory of CO2 Capture and TreatmentBeijing Key Laboratory of CO2 Capture and TreatmentIn situ gas content is an important parameter associating coalbed methane, while the influence of pressure and temperature on methane adsorption and desorption still needs to be revealed. In this study, the molecular structure and methane adsorption capacity of anthracite coal collected from Diandong Coalfield (China) were studied based on 13C nuclear magnetic resonance (13C NMR), Fourier transform infrared spectroscopy (FT-IR), and methane isothermal adsorption experiment. The results show that the carbon skeleton of coal sample is mainly composed by aromatic carbon (72%), followed by aliphatic carbon structure (14.2%). Carbons connected to the oxygen atoms contribute 13.7% of the total carbons in coal molecule, and the oxygen atoms are mainly in the form of carbonyl. The 2-dimension structure and 3-dimension molecular structure of coal sample was also reconstructed. The average chemical formula of the coal molecule is C200H133O21N3. The experimental methane adsorption isothermal data of the coal sample under different temperatures shows that with increasing the temperature, the methane adsorption amount at each pressure decreases obviously. At 7 MPa and 20°C, the methane adsorption amount of the coal sample is 28.5 cm3/g. Comparably, at 100°C and 7 MPa, the methane adsorption amount is only 15.9 cm3/g, decreasing by 44%. In mesopores, temperature has stronger influence on methane adsorption under higher pressure than that of lower pressure. On the contrary, in micropores, temperature has weaker effects on methane adsorption at higher pressure than that at lower pressure. The results can be beneficial for understanding methane adsorption characteristics of deep coal.http://dx.doi.org/10.1155/2023/8528359
spellingShingle Tieya Jing
Jian Zhang
Mingyu Zhu
Wentao Zhao
Juan Zhou
Yulong Yin
Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular Simulation
Geofluids
title Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular Simulation
title_full Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular Simulation
title_fullStr Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular Simulation
title_full_unstemmed Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular Simulation
title_short Methane Adsorption in Anthracite Coal under Different Pressures and Temperatures—A Study Combining Isothermal Adsorption and Molecular Simulation
title_sort methane adsorption in anthracite coal under different pressures and temperatures a study combining isothermal adsorption and molecular simulation
url http://dx.doi.org/10.1155/2023/8528359
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AT jianzhang methaneadsorptioninanthracitecoalunderdifferentpressuresandtemperaturesastudycombiningisothermaladsorptionandmolecularsimulation
AT mingyuzhu methaneadsorptioninanthracitecoalunderdifferentpressuresandtemperaturesastudycombiningisothermaladsorptionandmolecularsimulation
AT wentaozhao methaneadsorptioninanthracitecoalunderdifferentpressuresandtemperaturesastudycombiningisothermaladsorptionandmolecularsimulation
AT juanzhou methaneadsorptioninanthracitecoalunderdifferentpressuresandtemperaturesastudycombiningisothermaladsorptionandmolecularsimulation
AT yulongyin methaneadsorptioninanthracitecoalunderdifferentpressuresandtemperaturesastudycombiningisothermaladsorptionandmolecularsimulation