Effect of Pt Addition on Sulfur Dioxide and Water Vapor Tolerance of Pd-Mn-Hexaaluminate Catalysts for High-Temperature Oxidation of Methane
Научная публикация
| Общее |
Язык:
Английский,
Жанр:
Статья (Full article),
Статус опубликования:
Опубликована,
Оригинальность:
Оригинальная
|
| Журнал |
Applied Catalysis B: Environmental
ISSN: 0926-3373
, E-ISSN: 1873-3883
|
| Вых. Данные |
Год: 2017,
Том: 204,
Страницы: 89-106
Страниц
: 18
DOI:
10.1016/j.apcatb.2016.11.018
|
| Ключевые слова |
Methane oxidation, Mn-hexaaluminate, Pd-catalyst, Pt-catalyst, Sulfur-resistance |
| Авторы |
Yashnik S.A.
1
,
Chesalov Yu.A.
1,2
,
Ishchenko A.V.
1
,
Kaichev V.V.
1,2
,
Ismagilov Z.R.
1,3
|
| Организации |
| 1 |
Boreskov Institute of Catalysis, Lavrentieva Ave. 5, Novosibirsk, 630090, Russia
|
| 2 |
Novosibirsk State University, Pirogova Str. 2, Novosibirsk, 630090, Russia
|
| 3 |
Institute of Coal Chemistry and Material Science, Sovetskiy Ave. 18, Kemerovo, 650000, Russia
|
|
Информация о финансировании (1)
|
1
|
Российский фонд фундаментальных исследований
|
15-03-05459
|
An effect of Pt addition to improve the catalytic performance of Pd-modified Mn-hexaaluminate in the
high-temperature oxidation of methane, especially in SO2 and water presence, has been studied. X-ray
diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, thermogravimetry and differential thermal analysis were used for the characterization of fresh and spent
catalysts. Temperature-programmed reduction by hydrogen was employed to study the redox properties
of the catalysts. Four high-temperature tests (at 670 ◦C) of the methane oxidation were applied to reveal
the water and sulfur resistance ofthe catalysts: 1) dry methane-air feed; 2) wet methane-air feed containing
3 wt% of water vapor; 3) methane-air feed containing 1000 ppm of SO2; and 4) wet methane-air feed
with 1000 ppm of SO2. The Pt-doped Pd-Mn-hexaaluminate catalyst with the atomic ratio of Pt/Pd < 0.3
has been shown to possess the highest catalytic activity in the oxidation of methane, high water and
sulfur tolerance, and reducibility by hydrogen as compared to the monometallic Pd-Mn-hexaaluminate
catalyst and the bimetallic catalysts with Pt/Pd > 0.5. From the formal kinetic data of the oxidation of
methane on the fresh and deactivated catalysts, we assumed that deactivation of the catalysts is due to
a decrease in the amount of catalytically active sites in the bimetallic 0.33Pt-0.67Pd(0.27)/MnLaAl11O19
catalyst and a change in the state of active component in the other catalysts. Their oxidation ability and
redox behavior were shown to be associated with the highly dispersed PdO particles, a PdO layer (3–5 nm)
covering the metal palladium particles as well as the Mn3+-enriched MnLaAl11O19. The improved water
and sulfur resistance is found to correlate with the presence of particles of PtPd alloy, with its fraction
not exceeding 50%.