Mn2NiO4 spinel catalyst for high-efficiency selective catalytic reduction of nitrogen oxides with good resistance to H2O and SO2 at low temperature.
J Environ Sci (China)
; 89: 145-155, 2020 Mar.
Article
em En
| MEDLINE
| ID: mdl-31892387
Mn-Ni oxides with different compositions were prepared using standard co-precipitation (CP) and urea hydrolysis-precipitation (UH) methods and optimized for the selective catalytic reduction of nitrogen oxides (NOx) by NH3 at low temperature. Mn(2)Ni(1)Ox-CP and Mn(2)Ni(1)Ox-UH (with Mn:Ni molar ratio of 2:1) catalysts showed almost identical selective catalytic reduction (SCR) catalytic activity, with about 96% NOx conversion at 75°C and ~99% in the temperature range from 100 to 250°C. X-ray diffraction (XRD) results showed that Mn(2)Ni(1)Ox-CP and Mn(2)Ni(1)Ox-UH catalysts crystallized in the form of Mn2NiO4 and MnO2-Mn2NiO4 spinel, respectively. The latter gave relatively good selectivity to N2, which might be due to the presence of the MnO2 phase and high metal-O binding energy, resulting in low dehydrogenation ability. According to the results of various characterization methods, it was found that a high density of surface chemisorbed oxygen species and efficient electron transfer between Mn and Ni in the crystal structure of Mn2NiO4 spinel played important roles in the high-efficiency SCR activity of these catalysts. Mn(2)Ni(1)Ox catalysts presented good resistance to H2O or/and SO2 with stable activity, which benefited from the Mn2NiO4 spinel structure and Eley-Rideal mechanism, with only slight effects from SO2.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Óxidos
/
Dióxido de Enxofre
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Compostos de Manganês
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Óxidos de Nitrogênio
Idioma:
En
Revista:
J Environ Sci (China)
Assunto da revista:
SAUDE AMBIENTAL
Ano de publicação:
2020
Tipo de documento:
Article
País de afiliação:
China