Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestration
Significant progress has recently been made in carbon sequestration in unmineable coal seams, including the coal physicochemical properties and environmental parameters that may affect the sequestration process. However, the effect of prolonged exposure to a flue gas on the pore structural changes o...
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| Format: | Article |
| Language: | English |
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Elsevier
2023-06-01
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| Series: | Carbon Capture Science & Technology |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2772656823000192 |
| _version_ | 1797807171304423424 |
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| author | Major Mabuza Kasturie Premlall |
| author_facet | Major Mabuza Kasturie Premlall |
| author_sort | Major Mabuza |
| collection | DOAJ |
| description | Significant progress has recently been made in carbon sequestration in unmineable coal seams, including the coal physicochemical properties and environmental parameters that may affect the sequestration process. However, the effect of prolonged exposure to a flue gas on the pore structural changes of coals have not yet been considered. This study presents textural properties of two coals from South African coalfields probed using low-pressure gas adsorption (LPGA) of carbon dioxide (CO2) and nitrogen (N2) after flue gas exposure. The coals were obtained from Somkhele and Ermelo coalfields and were subjected to a flue gas synthesized to resemble that of a coal-fired power plant comprising 82% N2, 12% CO2, 5.5% O2, 0.38% SO2, and 0.12% NO2 on short-term (120 h) and long-term (2 232 h) basis. The coal samples were subjected to a flue gas at a high-pressure of 9.0 MPa and a temperature of 60 °C using a volumetric sorption system. After flue gas exposure, the surface area of the coals reduced by a maximum of 39% mainly owing to the reduced active sites. The micropore size distribution pattern for the coals maintained the original shape after being exposed to the flue gas with the pores distributed within a size range of 0.30 and 0.50 nm, showing the existence of narrow micropores in the coals; however, the highest peak value reduced by up to 17.7% relative to untreated coals. The mesopore size distribution acquired from the flue gas treated coals ranges from 1.6 nm to 2.4 nm, validating the existence of wide mesopores yielding an increase in the differential pore volume capacity relative to untreated coals. |
| first_indexed | 2024-03-13T06:18:33Z |
| format | Article |
| id | doaj.art-4e6b9093a54e499ab75fa3c64d5a68f4 |
| institution | Directory Open Access Journal |
| issn | 2772-6568 |
| language | English |
| last_indexed | 2024-03-13T06:18:33Z |
| publishDate | 2023-06-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Carbon Capture Science & Technology |
| spelling | doaj.art-4e6b9093a54e499ab75fa3c64d5a68f42023-06-10T04:29:03ZengElsevierCarbon Capture Science & Technology2772-65682023-06-017100115Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestrationMajor Mabuza0Kasturie Premlall1Department of Chemical Engineering Technology, Faculty of Engineering and the Built Environment, University of Johannesburg, P.O. Box 17011, Doornfontein, Johannesburg 2088, South Africa; Corresponding author.Department of Chemical, Metallurgical and Materials Engineering, Faculty of Engineering and the Built Environment, Tshwane University of Technology, Private Bag X680, Pretoria 0001, South AfricaSignificant progress has recently been made in carbon sequestration in unmineable coal seams, including the coal physicochemical properties and environmental parameters that may affect the sequestration process. However, the effect of prolonged exposure to a flue gas on the pore structural changes of coals have not yet been considered. This study presents textural properties of two coals from South African coalfields probed using low-pressure gas adsorption (LPGA) of carbon dioxide (CO2) and nitrogen (N2) after flue gas exposure. The coals were obtained from Somkhele and Ermelo coalfields and were subjected to a flue gas synthesized to resemble that of a coal-fired power plant comprising 82% N2, 12% CO2, 5.5% O2, 0.38% SO2, and 0.12% NO2 on short-term (120 h) and long-term (2 232 h) basis. The coal samples were subjected to a flue gas at a high-pressure of 9.0 MPa and a temperature of 60 °C using a volumetric sorption system. After flue gas exposure, the surface area of the coals reduced by a maximum of 39% mainly owing to the reduced active sites. The micropore size distribution pattern for the coals maintained the original shape after being exposed to the flue gas with the pores distributed within a size range of 0.30 and 0.50 nm, showing the existence of narrow micropores in the coals; however, the highest peak value reduced by up to 17.7% relative to untreated coals. The mesopore size distribution acquired from the flue gas treated coals ranges from 1.6 nm to 2.4 nm, validating the existence of wide mesopores yielding an increase in the differential pore volume capacity relative to untreated coals.http://www.sciencedirect.com/science/article/pii/S2772656823000192Low-pressureGas adsorptionPore structural propertiesCoalFlue gas exposure |
| spellingShingle | Major Mabuza Kasturie Premlall Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestration Carbon Capture Science & Technology Low-pressure Gas adsorption Pore structural properties Coal Flue gas exposure |
| title | Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestration |
| title_full | Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestration |
| title_fullStr | Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestration |
| title_full_unstemmed | Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestration |
| title_short | Alterations in the textural structural properties of coals exposed to flue gas for long-term carbon sequestration |
| title_sort | alterations in the textural structural properties of coals exposed to flue gas for long term carbon sequestration |
| topic | Low-pressure Gas adsorption Pore structural properties Coal Flue gas exposure |
| url | http://www.sciencedirect.com/science/article/pii/S2772656823000192 |
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