Molecular simulation and experimental studies on CO2 and N2 adsorption to bituminous coal

Zhu, Huangqiu; Guo, Song; Xie, Yuyi; Zhao, Hongjin

doi:10.1007/s11356-020-11722-y

Cited by 15 publications

(12 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Density is one of the most basic physical properties of coal and rock, and it is an important basis for evaluating whether the coal rock structure model is reasonable . The periodic boundary conditions of coking coal macromolecules are established by the Amorphous Cell calculation module in Materials Studio. , The simulated density was set in the range of 0.5–1.5 g/cm 3 . To choose the optimal density, the density increase step in the range of 0.5–1 g/cm 3 was set to 0.1 and the density increase step in the range of 1–1.5 g/cm 3 was set to 0.05.…”

Section: Molecular Simulation Test Results and Analysismentioning

confidence: 99%

Study on Adsorption Characteristics of Deep Coking Coal Based on Molecular Simulation and Experiments

et al. 2023

View full text Add to dashboard Cite

To study the effect of high temperature and high pressure on the adsorption characteristics of coking coal, Liulin coking coal and Pingdingshan coking coal were selected as the research objects, and isotherm adsorption curves at different temperatures and pressures were obtained by combining isotherm adsorption experiments and molecular dynamics methods. The effect of high temperature and high pressure on the adsorption characteristics of coking coal was analyzed, and an isothermal adsorption model suitable for hightemperature and high-pressure conditions was studied. The results show that the adsorption characteristics of deep coking coal can be well characterized by the molecular dynamics method. Under a supercritical condition, the excess adsorption capacity of methane decreases with the increase of temperature. With the increase of pressure, the excess adsorption capacity rapidly increases in the early stage, temporarily stabilizes in the middle stage, and decreases in the later stage. Based on the classical adsorption model, the adsorption capacity of coking coal under high-temperature and high-pressure environments is fitted. The fitting degree ranges from good to poor. The order is D−R > D−A > L−F >BET > Langmuir, and combined with temperature gradient, pressure gradient, and the D−R adsorption model, it can be seen that after 800 m deep in Liulin Mine and 400 m deep in Pingdingshan Mine, the adsorption capacity of coking coal to methane decreases with the increase of depth.

show abstract

Section: Molecular Simulation Test Results and Analysismentioning

confidence: 99%

Study on Adsorption Characteristics of Deep Coking Coal Based on Molecular Simulation and Experiments

et al. 2023

View full text Add to dashboard Cite

show abstract

“…A basic structural unit was used to construct the bituminous coal pore model, and this modeling approach has been widely used. ,,, The total size of the model was set to 4 × 4 × 2.5 nm 3 , and five basic structural units were added. The pore diameter at the center of the model was set to 3 nm; however, owing to the bending and folding of the aromatic sheet layer, irregular concave and convex surfaces were formed around the pores, so the actual pore width after construction was slightly larger than 3 nm.…”

Section: Model Constructionmentioning

confidence: 99%

Modeling Methane Adsorption Distance Using Carbon Nanotubes and Bituminous Coal Pore Models

Zha,

Lin,

Liu

et al. 2024

Energy Fuels

View full text Add to dashboard Cite

To simplify the analysis of the adsorption of methane by coal, single-walled carbon nanotubes (SWCNTs), slit graphene lamellae, and bituminous coal pore models were constructed, and the adsorption of methane molecules in the three models was studied using molecular dynamics and density functional theory. The results show that methane molecules cannot be adsorbed within carbon nanotubes with a pore size of 0.5 nm. In carbon nanotubes with a pore size of 1 nm, adsorbed methane is influenced by the inner wall of the SWCNTs to induce dipoles and to interact with nearby methane molecules. In large-pore-size carbon nanotubes and graphene sheets, methane molecules adsorb and accumulate on the wall surface to form adsorption rings, the thickness of which gradually increases with the pore size under the effect of curvature, ranging from 0.455 to 0.521 nm. This criterion for adsorption was applied to the pore model of bituminous coal, and 52 adsorbed methane states were determined. Furthermore, the Brunauer–Emmett–Teller equation was used to fit the methane isothermal adsorption curve of the bituminous coal pore model, and the adsorption quantity of methane in a single molecular layer was 54, confirming that the adsorption criterion of 0.521 nm is reasonable.

show abstract

“…There are many studies on the microscopic mechanism of gas adsorption, ,− most of which are based on the unit cell structure of coal molecules or the graphene model. However, coal is a porous medium, and the pores in coal are rarely considered, so it cannot reflect the real adsorption of gas in the pores.…”

Section: Introductionmentioning

confidence: 99%

Study of Adsorption Characteristics of CO₂, O₂, and N₂ in Coal Micropores and Mesopores at Normal Pressure

Tan

Cheng

et al. 2022

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

At present, there are few studies on the adsorption laws of multicomponent gases in different pores of coal. This study takes AW (gas coal), YH (long-flame coal), and HL (lignite) coal samples as the research objects, and their molecular models are constructed by means of elemental analysis, 13 C NMR, and X-ray. The experimental results of low-pressure nitrogen gas adsorption experiment were used to analyze the pore size distribution characteristics of coal and serve as the basis for establishing the corresponding micropore and mesopore structures. At 303 K and 0.1 MPa, the adsorption characteristics of coal in the ternary system of CO 2 , O 2 , and N 2 were studied by the breakthrough experiments and gas adsorption simulations in different pores. The adsorption breakthrough curves and kinetic characteristics of the three gases were analyzed from a macroscopic point of view; the adsorption potential energy, adsorption density, adsorption amount, isosteric heat, and diffusion coefficient of the three gases in different pores of coal were compared from a microscopic point of view. It is found that the adsorption capacity of CO 2 in the pores of the three types of coals is far greater than that of N 2 and O 2 . The specific surface area and volume of pores have a significant effect on the displacement of CO 2 and N 2 on O 2 . The change of pore size has a significant effect on gas adsorption. In 0.4−5 nm pores, with the expansion of pore size, the value of gas adsorption and adsorption potential energy first decreases and then increases, the isosteric heat and the maximum adsorption density gradually decrease, and the self-diffusion coefficient shows an upward trend. The simulation results display a good agreement with the experimental results. This study is expected to provide some theoretical support for CO 2 and N 2 injection to prevent coal spontaneous combustion.

show abstract

Molecular simulation and experimental studies on CO2 and N2 adsorption to bituminous coal

Cited by 15 publications

References 28 publications

Study on Adsorption Characteristics of Deep Coking Coal Based on Molecular Simulation and Experiments

Study on Adsorption Characteristics of Deep Coking Coal Based on Molecular Simulation and Experiments

Modeling Methane Adsorption Distance Using Carbon Nanotubes and Bituminous Coal Pore Models

Study of Adsorption Characteristics of CO₂, O₂, and N₂ in Coal Micropores and Mesopores at Normal Pressure

Contact Info

Product

Resources

About

Molecular simulation and experimental studies on CO2 and N2 adsorption to bituminous coal

Cited by 15 publications

References 28 publications

Study on Adsorption Characteristics of Deep Coking Coal Based on Molecular Simulation and Experiments

Study on Adsorption Characteristics of Deep Coking Coal Based on Molecular Simulation and Experiments

Modeling Methane Adsorption Distance Using Carbon Nanotubes and Bituminous Coal Pore Models

Study of Adsorption Characteristics of CO2, O2, and N2 in Coal Micropores and Mesopores at Normal Pressure

Contact Info

Product

Resources

About

Study of Adsorption Characteristics of CO₂, O₂, and N₂ in Coal Micropores and Mesopores at Normal Pressure