Revisiting the concepts of competition between reaction and diffusion in poisoned catalysts

• Tipo: Artigo em Revista Científica Internacional
• Data: 2013

Autores

Luís M. Madeira (Autor) FEUP; Alírio E. Rodrigues (Autor) FEUP

Revista

Título: Canadian Journal of Chemical Engineering

Vol. 91 Nº 2

Páginas: 203-211

ISSN: 0008-4034

Editora: Wiley-Blackwell

Indexação

ISI Web of Knowledge - 1 Citação

ISI Web of Science

Scopus - 1 Citação

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Engenharia química

CORDIS: Ciências Tecnológicas > Engenharia > Engenharia química

Outras Informações

ID Authenticus: P-002-12G

DOI: 10.1002/cjce.21759

Abstract (EN): The competition between diffusion and first-order irreversible reaction in poisoned catalysts is revisited. Two cases are considered for isothermal slab catalysts: uniform and shell-progressive (or pore-mouth) poisoning. Analytical concentration profiles are derived, and the implications on catalyst performance are evaluated in different regimes (chemical- or diffusion-controlled) for different levels of poisoning. It was found that depending on the poisoning mechanism, the activity decay can be more or less pronounced. Being of particular concern is the pore-mouth poisoning at high Thiele modulus, conditions under which catalyst performance is drastically affected. The reagent concentration profiles allowed the explanation of the phenomena occurring at the particle scale, in particular the effectiveness factors, observed reaction rates, and poisoning factors' dependence on the Thiele modulus and fraction of the poisoned catalyst; it was found that such relationships are dependent on the mechanism of deactivation. (c) 2012 Canadian Society for Chemical Engineering

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 9