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Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect

In this study, microwave-assisted ammonia decomposition reaction was investigated over molybdenum incorporated catalysts. Due to the selective, volumetric, and noncontact heating properties of the microwave system, higher conversion values could be achieved at relatively lower reaction temperatures,...

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Autores principales: GÜLER, Melih, VARIŞLI, Dilek
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Scientific and Technological Research Council of Turkey 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7668040/
https://www.ncbi.nlm.nih.gov/pubmed/33488159
http://dx.doi.org/10.3906/kim-1907-4
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author GÜLER, Melih
VARIŞLI, Dilek
author_facet GÜLER, Melih
VARIŞLI, Dilek
author_sort GÜLER, Melih
collection PubMed
description In this study, microwave-assisted ammonia decomposition reaction was investigated over molybdenum incorporated catalysts. Due to the selective, volumetric, and noncontact heating properties of the microwave system, higher conversion values could be achieved at relatively lower reaction temperatures, which is important for on-site COx-free hydrogen production. Multiwall carbon nanotube-supported molybdenum catalysts were prepared following the impregnation procedure with different metal loading (3.5%–12.5% wt%), and inductively coupled plasma, nitrogen physisorption, X-ray diffraction, and transmission electron microscopic techniques were employed to characterize the fresh and used samples. Reaction experiments were performed under the flow of pure ammonia with a gas hourly space velocity of 36,000 mL/g(cat.)h for both the microwave and conventionally heated reaction systems. It was found that ammonia conversion was obtained even at 400 °C, reaching 40%, and total conversion was observed even at 450 °C, while the activities of these catalysts were negligible at a reaction temperature lower than 550 °C, in the conventional heated system, which included an electrically heated furnace. Crystals of α-Mo(2)C as well as MoO(2) were observed in the structures of the synthesized catalysts and the formation of nitride species was more easily observable under microwave heating, possibly due to the nitridation of molybdenum carbide species during the reaction.
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spelling pubmed-76680402021-01-22 Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect GÜLER, Melih VARIŞLI, Dilek Turk J Chem Article In this study, microwave-assisted ammonia decomposition reaction was investigated over molybdenum incorporated catalysts. Due to the selective, volumetric, and noncontact heating properties of the microwave system, higher conversion values could be achieved at relatively lower reaction temperatures, which is important for on-site COx-free hydrogen production. Multiwall carbon nanotube-supported molybdenum catalysts were prepared following the impregnation procedure with different metal loading (3.5%–12.5% wt%), and inductively coupled plasma, nitrogen physisorption, X-ray diffraction, and transmission electron microscopic techniques were employed to characterize the fresh and used samples. Reaction experiments were performed under the flow of pure ammonia with a gas hourly space velocity of 36,000 mL/g(cat.)h for both the microwave and conventionally heated reaction systems. It was found that ammonia conversion was obtained even at 400 °C, reaching 40%, and total conversion was observed even at 450 °C, while the activities of these catalysts were negligible at a reaction temperature lower than 550 °C, in the conventional heated system, which included an electrically heated furnace. Crystals of α-Mo(2)C as well as MoO(2) were observed in the structures of the synthesized catalysts and the formation of nitride species was more easily observable under microwave heating, possibly due to the nitridation of molybdenum carbide species during the reaction. The Scientific and Technological Research Council of Turkey 2020-04-01 /pmc/articles/PMC7668040/ /pubmed/33488159 http://dx.doi.org/10.3906/kim-1907-4 Text en Copyright © 2020 The Author(s) This article is distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/4.0/ ), which permits unrestricted use and redistribution provided that the original author and source are credited.
spellingShingle Article
GÜLER, Melih
VARIŞLI, Dilek
Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect
title Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect
title_full Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect
title_fullStr Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect
title_full_unstemmed Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect
title_short Multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect
title_sort multiwall carbon nanotube-supported molybdenum catalysts for ammonia decomposition reaction under microwave effect
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7668040/
https://www.ncbi.nlm.nih.gov/pubmed/33488159
http://dx.doi.org/10.3906/kim-1907-4
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