Mechanochemical Synthesis and Catalytic Properties of the Calcium Ferrite Ca2Fe2O5
Научная публикация
| Общее |
Язык:
Английский,
Жанр:
Статья (Full article),
Статус опубликования:
Опубликована,
Оригинальность:
Переводная
|
| Журнал |
Kinetics and Catalysis
ISSN: 0023-1584
, E-ISSN: 1608-3210
|
| Вых. Данные |
Год: 2002,
Том: 43,
Номер: 1,
Страницы: 122-128
Страниц
: 7
DOI:
10.1023/A:1014217716883
|
| Авторы |
Isupova L.A.
1
,
Tsybulya S.V.
1
,
Kryukova G.N.
1
,
Budneva A.A.
1
,
Paukshtis E.A.
1
,
Litvak G.S.
1
,
Ivanov V.P.
1
,
Kolomiichuk V.N.
1
,
Pavlyukhin Y.T.
2
,
Sadykov V.A.
1
|
| Организации |
| 1 |
Boreskov Institute of Catalysis, Siberian Division, Russian Academy of Sciences, Novosibirsk, 630090 Russia
|
| 2 |
Institute of Solid-State Chemistry, Siberian Division, Russian Academy of Sciences, Novosibirsk, 630128 Russia
|
|
Информация о финансировании (1)
|
1
|
Российский фонд фундаментальных исследований
|
99-03-32836
|
The formation of the real structure of calcium ferrite prepared by the calcination of a mechanochemically activated hydroxide mixture at 600–1100°C was studied by X-ray diffraction analysis, electron microscopy, thermal analysis, Moessbauer spectroscopy, IR spectroscopy, small-angle X-ray scattering, and secondary-ion mass spectrometry. It was found that low-temperature calcium ferrite is an anion-modified oxide, in which the ordering of oxygen vacancies was incomplete. Regions with a disordered structure were detected on the surface of crystallites. As the calcination temperature was increased, the brownmillerite crystal structure was improved and the intercrystalline boundaries were formed and then annealed. At the surface, these processes were accompanied by a change in the predominant form of adsorbed NO from nitrosyl to dinitrosyl species. An increase in the specific catalytic activity of samples with calcination temperature can be associated with the perfection of the brownmillerite structure and with a change in the state of adsorption centers.