Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes
Early catalyst deactivation through the encapsulation of catalyst nanoparticles by amorphous carbon layer due to the oversupply of carbon source is one of the key elements that inhibit efficient carbon nanotubes (CNT) synthesis in flame environment. The present study utilizes methane diffusion flame...
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| Format: | Article |
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Elsevier Inc.
2020
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| _version_ | 1796865476363550720 |
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| author | Hamzah, Norikhwan Mohd. Yasin, Mohd. Fairus Mohd. Yusop, Mohd. Zamri Mohammad Haniff, Muhammad Aniq Shazni Hasan, Mohd. Faizal Tamrin, Khairul Fikri Mohd. Subha, Nurul Adilla |
| author_facet | Hamzah, Norikhwan Mohd. Yasin, Mohd. Fairus Mohd. Yusop, Mohd. Zamri Mohammad Haniff, Muhammad Aniq Shazni Hasan, Mohd. Faizal Tamrin, Khairul Fikri Mohd. Subha, Nurul Adilla |
| author_sort | Hamzah, Norikhwan |
| collection | ePrints |
| description | Early catalyst deactivation through the encapsulation of catalyst nanoparticles by amorphous carbon layer due to the oversupply of carbon source is one of the key elements that inhibit efficient carbon nanotubes (CNT) synthesis in flame environment. The present study utilizes methane diffusion flame with water vapor additive to analyze the effectiveness of the novel water-assisted synthesis of CNT in reducing amorphous carbon formation. Flame shape, temperature, and CNT growth region within the water-assisted flame were analyzed at varying fuel and oxygen concentration. The amorphous carbon layer thickness (ACLT) is analyzed through cross-sectional analysis of the CNT growth region using a developed bend wire method. A 50% increase in fuel concentration results in the increase in axial extent of the growth region by 37.5% followed by an increase in the ACLT by 20%. Meanwhile, an 8% increase in oxygen concentration results in the decrease of growth region axial extent by 82% with a 35% reduction in ACLT. On average, water vapor additive produces an additional 17.3% reduction in ACLT in any flame composition. Both the reduction in ACLT as oxygen and water concentration is independently increased happen due to the carbon supply regulation. However, since the change in the growth temperature that happens at varying oxygen concentration is not observed at varying water concentration, the carbon supply regulation in both situations is remarkably different as explained by the water-gas shift reaction. |
| first_indexed | 2024-03-05T20:57:35Z |
| format | Article |
| id | utm.eprints-92702 |
| institution | Universiti Teknologi Malaysia - ePrints |
| last_indexed | 2024-03-05T20:57:35Z |
| publishDate | 2020 |
| publisher | Elsevier Inc. |
| record_format | dspace |
| spelling | utm.eprints-927022021-10-28T10:25:21Z http://eprints.utm.my/92702/ Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes Hamzah, Norikhwan Mohd. Yasin, Mohd. Fairus Mohd. Yusop, Mohd. Zamri Mohammad Haniff, Muhammad Aniq Shazni Hasan, Mohd. Faizal Tamrin, Khairul Fikri Mohd. Subha, Nurul Adilla TJ Mechanical engineering and machinery Early catalyst deactivation through the encapsulation of catalyst nanoparticles by amorphous carbon layer due to the oversupply of carbon source is one of the key elements that inhibit efficient carbon nanotubes (CNT) synthesis in flame environment. The present study utilizes methane diffusion flame with water vapor additive to analyze the effectiveness of the novel water-assisted synthesis of CNT in reducing amorphous carbon formation. Flame shape, temperature, and CNT growth region within the water-assisted flame were analyzed at varying fuel and oxygen concentration. The amorphous carbon layer thickness (ACLT) is analyzed through cross-sectional analysis of the CNT growth region using a developed bend wire method. A 50% increase in fuel concentration results in the increase in axial extent of the growth region by 37.5% followed by an increase in the ACLT by 20%. Meanwhile, an 8% increase in oxygen concentration results in the decrease of growth region axial extent by 82% with a 35% reduction in ACLT. On average, water vapor additive produces an additional 17.3% reduction in ACLT in any flame composition. Both the reduction in ACLT as oxygen and water concentration is independently increased happen due to the carbon supply regulation. However, since the change in the growth temperature that happens at varying oxygen concentration is not observed at varying water concentration, the carbon supply regulation in both situations is remarkably different as explained by the water-gas shift reaction. Elsevier Inc. 2020-10 Article PeerReviewed Hamzah, Norikhwan and Mohd. Yasin, Mohd. Fairus and Mohd. Yusop, Mohd. Zamri and Mohammad Haniff, Muhammad Aniq Shazni and Hasan, Mohd. Faizal and Tamrin, Khairul Fikri and Mohd. Subha, Nurul Adilla (2020) Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes. Combustion and Flame, 220 . pp. 272-287. ISSN 0010-2180 http://dx.doi.org/10.1016/j.combustflame.2020.07.007 DOI:10.1016/j.combustflame.2020.07.007 |
| spellingShingle | TJ Mechanical engineering and machinery Hamzah, Norikhwan Mohd. Yasin, Mohd. Fairus Mohd. Yusop, Mohd. Zamri Mohammad Haniff, Muhammad Aniq Shazni Hasan, Mohd. Faizal Tamrin, Khairul Fikri Mohd. Subha, Nurul Adilla Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes |
| title | Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes |
| title_full | Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes |
| title_fullStr | Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes |
| title_full_unstemmed | Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes |
| title_short | Effect of fuel and oxygen concentration toward catalyst encapsulation in water-assisted flame synthesis of carbon nanotubes |
| title_sort | effect of fuel and oxygen concentration toward catalyst encapsulation in water assisted flame synthesis of carbon nanotubes |
| topic | TJ Mechanical engineering and machinery |
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