Green hydrogen from catalytic ammonia decomposition

Ir/γ-alumina catalysts for decomposition of ammonia were prepared by Iridium ion exchange procedure, onto γ-alumina synthesized by sol-gel method. In order to determine the physical and chemical properties we used X ray diffraction (XRD) analysis, Fourier transformed infrared spectroscopy (FTIR), sc...

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Autores principales: Gómez Costa, Marcos B., Juárez, Juliana M., Anunziata, Oscar A.
Formato: Documento de conferencia publisherVersion
Lenguaje:Inglés
Publicado: 2022
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12272/6590
Aporte de:
id I68-R174-20.500.12272-6590
record_format dspace
institution Universidad Tecnológica Nacional
institution_str I-68
repository_str R-174
collection RIA - Repositorio Institucional Abierto (UTN)
language Inglés
topic Ir/γ-alumina
Synthesis
Characterization
Ammonia Decomposition
Green H2
spellingShingle Ir/γ-alumina
Synthesis
Characterization
Ammonia Decomposition
Green H2
Gómez Costa, Marcos B.
Juárez, Juliana M.
Anunziata, Oscar A.
Green hydrogen from catalytic ammonia decomposition
topic_facet Ir/γ-alumina
Synthesis
Characterization
Ammonia Decomposition
Green H2
description Ir/γ-alumina catalysts for decomposition of ammonia were prepared by Iridium ion exchange procedure, onto γ-alumina synthesized by sol-gel method. In order to determine the physical and chemical properties we used X ray diffraction (XRD) analysis, Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nuclear magnetic resonance (NMR-MAS). The samples displayed the characteristic band at 1620 cm-1 corresponds to a N-H bending of ammonia adsorbed on electron-acceptor sites, and the characterization by pyridine adsorption and desorption to determine the presence of Lewis acid sites, with absence of Brønsted sites, showing higher acid strength than commercial sample used as reference. The analysis of particle size and morphology reveal uniformity, with tendency to a spheroid aspect and smaller to 3 μm of diameter. The 27Al NMR-MAS test, allowed determining the tetrahedral and octahedral aluminum presence in both samples, where the higher proportion of octahedral Al in γ-alumina synthesized by us, is correlated toward the greater electron acceptor acid sites. The designed method was effective for Ir/γ-alumina catalysts synthesis. The surface area was 150 and 260 m2/g for the commercial sample and the alumina prepared by and us, and after the Ir incorporation (10-18% w/w in both samples), they surfaces were reduced approximately 5.4-8.8% and 4.3-7.2% respectively. XRD analyses show the absence of maximums at 28º and 34.7º 2 corresponding to iridium oxide, indicating a high efficiency of the reduction treatment, increasing the active sites for the specific reaction of ammonia decomposition. The distribution of the Ir crystallites determined by XRD and TEM indicated that, the samples prepared by ion exchange method produced smaller Iridium clusters than by impregnation procedure of alumina sample, with higher surface area and greater anchorage sites. According to preliminary catalytic tests, the Ir/γ-alumina catalysts prepared by a novel method showed higher activity to ammonia decomposition to N2 and green H2.
format Documento de conferencia
publisherVersion
author Gómez Costa, Marcos B.
Juárez, Juliana M.
Anunziata, Oscar A.
author_facet Gómez Costa, Marcos B.
Juárez, Juliana M.
Anunziata, Oscar A.
author_sort Gómez Costa, Marcos B.
title Green hydrogen from catalytic ammonia decomposition
title_short Green hydrogen from catalytic ammonia decomposition
title_full Green hydrogen from catalytic ammonia decomposition
title_fullStr Green hydrogen from catalytic ammonia decomposition
title_full_unstemmed Green hydrogen from catalytic ammonia decomposition
title_sort green hydrogen from catalytic ammonia decomposition
publishDate 2022
url http://hdl.handle.net/20.500.12272/6590
work_keys_str_mv AT gomezcostamarcosb greenhydrogenfromcatalyticammoniadecomposition
AT juarezjulianam greenhydrogenfromcatalyticammoniadecomposition
AT anunziataoscara greenhydrogenfromcatalyticammoniadecomposition
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