Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 Catalyst

Trickle bed reactor was used to study the hydrogenation of nitrobenzene over Ni/SiO2 catalyst. The catalyst was prepared using the Highly Dispersed Catalyst (HDC) technique. Porous silica particles (capped cylinders, 6x5.5 mm) were used as catalyst support. The catalyst was characterized by TPR, BE...

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Main Author: Majid I. Abdulwahab
Format: Article
Language:English
Published: University of Baghdad 2023-06-01
Series:Journal of Engineering
Subjects:
Online Access:https://joe.uobaghdad.edu.iq/index.php/main/article/view/2293
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author Majid I. Abdulwahab
author_facet Majid I. Abdulwahab
author_sort Majid I. Abdulwahab
collection DOAJ
description Trickle bed reactor was used to study the hydrogenation of nitrobenzene over Ni/SiO2 catalyst. The catalyst was prepared using the Highly Dispersed Catalyst (HDC) technique. Porous silica particles (capped cylinders, 6x5.5 mm) were used as catalyst support. The catalyst was characterized by TPR, BET surface area and pore volume, X-ray diffraction, and Raman Spectra. The trickle bed reactor was packed with catalyst and diluted with fine glass beads in order to decrease the external effects such as mass transfer, heat transfer and wall effect. The catalyst bed dilution was found to double the liquid holdup, which increased the catalyst wetting and hence, the gas-liquid mass transfer rate. The main product of the hydrogenation reaction of nitrobenzene was aniline. Reaction operating conditions, i.e., temperature, liquid flow rate, and initial feed concentration were investigated to find their influences on the conversion and rate of nitrobenzene hydrogenation. Under normal conditions without bed dilution, the system was mass transfer controlled. In the diluted reactor, on the other hand, the resistance of mass transfer was nearly absent and the system became under surface kinetic control. The catalyst showed significant deactivation during the reaction period due to the adsorption of intermediate amine products on the surface of the catalyst. The kinetic study revealed that the reaction is zero order with respect to nitrobenzene concentration for the range of concentration between 0.58 to 1.17 mol/L while it was of positive order for the initial concentration less than 0.58 mol/L
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spelling doaj.art-f8a2beb5be7547c4bc049e73b9a85edc2023-07-11T18:34:27ZengUniversity of BaghdadJournal of Engineering1726-40732520-33392023-06-01191010.31026/j.eng.2013.10.09Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 CatalystMajid I. Abdulwahab Trickle bed reactor was used to study the hydrogenation of nitrobenzene over Ni/SiO2 catalyst. The catalyst was prepared using the Highly Dispersed Catalyst (HDC) technique. Porous silica particles (capped cylinders, 6x5.5 mm) were used as catalyst support. The catalyst was characterized by TPR, BET surface area and pore volume, X-ray diffraction, and Raman Spectra. The trickle bed reactor was packed with catalyst and diluted with fine glass beads in order to decrease the external effects such as mass transfer, heat transfer and wall effect. The catalyst bed dilution was found to double the liquid holdup, which increased the catalyst wetting and hence, the gas-liquid mass transfer rate. The main product of the hydrogenation reaction of nitrobenzene was aniline. Reaction operating conditions, i.e., temperature, liquid flow rate, and initial feed concentration were investigated to find their influences on the conversion and rate of nitrobenzene hydrogenation. Under normal conditions without bed dilution, the system was mass transfer controlled. In the diluted reactor, on the other hand, the resistance of mass transfer was nearly absent and the system became under surface kinetic control. The catalyst showed significant deactivation during the reaction period due to the adsorption of intermediate amine products on the surface of the catalyst. The kinetic study revealed that the reaction is zero order with respect to nitrobenzene concentration for the range of concentration between 0.58 to 1.17 mol/L while it was of positive order for the initial concentration less than 0.58 mol/L https://joe.uobaghdad.edu.iq/index.php/main/article/view/2293Hydrogenation, Trickle Bed, Nitrobenzene, Bed Dilution, Highly Dispersed Catalyst
spellingShingle Majid I. Abdulwahab
Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 Catalyst
Journal of Engineering
Hydrogenation, Trickle Bed, Nitrobenzene, Bed Dilution, Highly Dispersed Catalyst
title Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 Catalyst
title_full Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 Catalyst
title_fullStr Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 Catalyst
title_full_unstemmed Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 Catalyst
title_short Hydrogenation of Nitrobenzene in Trickle Bed Reactor over Ni/Sio2 Catalyst
title_sort hydrogenation of nitrobenzene in trickle bed reactor over ni sio2 catalyst
topic Hydrogenation, Trickle Bed, Nitrobenzene, Bed Dilution, Highly Dispersed Catalyst
url https://joe.uobaghdad.edu.iq/index.php/main/article/view/2293
work_keys_str_mv AT majidiabdulwahab hydrogenationofnitrobenzeneintricklebedreactorovernisio2catalyst