Selective catalytic reduction of NO to N2 with copper and cobalt exchanged ZSM-5 zeolites: the effect of calcium addition

Autor(es)

Leandro Martins ^[1] ; Robson Pablo S. Peguin ^[2] ; Martin Wallau ^[3] ; Ernesto Antonio Urquieta-González ^[4]

Afiliação do(s) autor(es)

^[1] Universidade Federal de São Carlos. Departamento de Engenharia Química - Brasil

^[2] Universidade Federal de São Carlos. Departamento de Engenharia Química - Brasil

^[3] Universidade Federal de São Carlos. Departamento de Engenharia Química - Brasil

^[4] Universidade Federal de São Carlos. Departamento de Engenharia Química - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 16, p. 589-596, 2005-06-00.

Resumo

ZSM-5 catalysts containing either Cu or Co cations individually or Cu/Ca or Co/Ca cation combinations were prepared by ion exchange. These materials were tested as catalysts for the reduction of NO to N2 in the presence of propane or methane. Cu2+ and [Cu-O-Cu]2+ species were identified in ion exchangeable sites in the copper-containing catalysts. The amount of the latter cation increased with increasing copper content and in the presence of Ca2+ and was the most active in the reduction of NO. However, at temperatures higher than 400 ºC its activity decreased markedly. For cobalt-exchanged zeolites, Co2+ in charge-compensation sites or Co3+ in extra-framework precipitates were present in the catalysts. It was verified that the amount of Co3+ diminished with the presence of Ca2+. For the catalysts prepared in this study no significant differences in specific activity for the reduction of NO or for methane oxidation were observed in the presence of calcium. (AU)

• Processo FAPESP: 00/06176-3 - Catalisadores cu/zsm-5 e co/zsm-5 para a reducao catalitica seletiva de no com hidrocarbonetos em efluentes gasosos contaminantes.
• Beneficiário: Leandro Pierroni Martins
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica