Hexaaluiminate-type catalysts for n2o abatement

Over the last decades, a large number of catalysts have been studied for catalytic decomposition of N2O. Most of these catalysts failed to be an alternative option for already commercialized counterparts and few of them showed reasonable activities under realistic conditions. Metal‐substit...

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Detalhes bibliográficos
Autor: Santiago Redondo, Marta
Tipo de documento: tese
Estado:Versão publicada
Data de publicação:2010
País:España
Recursos:Universitat Rovira i virgili (URV)
Repositório:Repositori Institucional de la Universitat Rovira i Virgili
OAI Identifier:oai:urv.cat:TDX:889
Acesso em linha:https://hdl.handle.net/20.500.11797/TDX889
http://hdl.handle.net/10803/9111
Access Level:Acceso aberto
Palavra-chave:546 - Química inorgànica
542 - Química pràctica de laboratori. Química preparativa i experimental
Descrição
Resumo:Over the last decades, a large number of catalysts have been studied for catalytic decomposition of N2O. Most of these catalysts failed to be an alternative option for already commercialized counterparts and few of them showed reasonable activities under realistic conditions. Metal‐substituted hexaaluminates, so far applied mainly in the catalytic combustion of methane in gas‐turbine applications, show excellent qualities as promising candidates for high‐temperature N2O abatement. Their layered structure together with the presence of redox sites provides chemical stability, high‐resistance to thermal shock and high activity. This thesis focuses on the development of metal‐substituted hexaaluminates, a novel catalytic system for high‐temperature N2O abatement. Synthesis, in situ thermal activation and characterization of metal‐substituted hexaaluminates have been carried out with the aim of gaining a better understanding of their formation. The catalytic activity was also evaluated simulating realistic conditions in both processes, i.e. nitric acid plant and stationary combustion. Additionally, an alternative route of synthesis, using templating approaches for the first time, has been successfully developed improving their catalytic activity. Finally, transient studies in the Temporal Analysis of Products (TAP) reactor have been carried out in order to gain insights into the N2O decomposition mechanism into N2 and O2.