Species active in the selective catalytic reduction of NO with iso-butane on iron-exchanged ZSM-5 zeolites



Document title: Species active in the selective catalytic reduction of NO with iso-butane on iron-exchanged ZSM-5 zeolites
Journal: Brazilian journal of chemical engineering
Database: PERIÓDICA
System number: 000308986
ISSN: 0104-6632
Authors: 1

Institutions: 1Universidade Federal de Sao Carlos, Departamento de Engenharia Quimica, Sao Carlos, Sao Paulo. Brasil
Year:
Season: Sep
Volumen: 22
Number: 3
Pages: 341-351
Country: Brasil
Language: Inglés
Document type: Artículo
Approach: Experimental, aplicado
English abstract Fe-ZSM-5 catalysts were prepared by ion exchange in aqueous medium or in the solid state and tested in the catalytic reduction of NO with iso-butane. X-ray powder diffraction (XRD), atomic absorption spectroscopy (AAS), electron paramagnetic resonance spectroscopy (EPR), X-ray absorption spectroscopy (XANES, EXAFS), temperature-programmed reduction by H2 (H2-TPR) and Mössbauer spectroscopy (MÖS-S) were used for sample characterisation. Irrespective of the method used in catalyst preparation, EPR, XANES and MÖS-S showed Fe atoms in the oxidation state of 3+. MÖS-S and H2-TPR data on Fe-ZSM-5 prepared by ion exchange in the solid state allowed quantification of a lower hematite (Fe2O3) concentration and a higher proportion of Fe cations than samples prepared in an aqueous medium. In all the catalysts studied these Fe cations were the active sites in the reduction of NO to N2 and in the oxidation of iso-butane. It is further suggested that coordination of Fe species is another important aspect to be considered in their behaviour
Disciplines: Química
Keyword: Ingeniería química,
Oxido nitroso,
Reducción catalítica selectiva,
Catalizadores,
Iso-butano,
Espectroscopía Mossbauer
Keyword: Chemistry,
Chemical engineering,
Nitrous oxide,
Selective catalytic reduction,
Catalysts,
Iso-butane,
Mossbauer spectroscopy
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