δ-Alumina Supported Cobalt Catalysts Promoted by Ruthenium for Fischer-Tropsch Synthesis
Full article
| Общее |
Language:
Английский,
Genre:
Full article,
Status:
Published,
Source type:
Original
|
| Journal |
Applied Catalysis A: General
ISSN: 0926-860X
, E-ISSN: 1873-3875
|
| Output data |
Year: 2017,
Volume: 539,
Pages: 48-58
Pages count
: 11
DOI:
10.1016/j.apcata.2017.04.003
|
| Tags |
Cobalt-alumina catalysts, Cobalt-ruthenium alloy, Fischer-Tropsch synthesis, Promotion, Ruthenium |
| Authors |
Kungurova Olga A.
1,2,3
,
Khassin Alexander A.
1,4
,
Cherepanova Svetlana V.
1,2
,
Saraev Andrey A.
1,2
,
Kaichev Vasily V.
1,2
,
Shtertser Natalya V.
1
,
Chermashentseva Galina K.
1
,
Gerasimov Еvgeny Yu.
1,2
,
Paukshtis Еvgeny A.
1
,
Vodyankina Оlga V.
3
,
Minyukova Tatyana P.
1
,
Abou-Jaoudé Georges
4
|
| Affiliations |
| 1 |
Boreskov Institute of Catalysis, 5, Lavrentieva Ave., Novosibirsk, 630090, Russia
|
| 2 |
Novosibirsk National Research University, 2, Pirogova Str., Novosibirsk, 630090, Russia
|
| 3 |
Tomsk State University, 36, Lenina Ave., Tomsk, 634050, Russia
|
| 4 |
École polytechnique fédérale de Lausanne, Route Cantonale, CH-1015 Lausanne, Switzerland
|
|
Funding (1)
|
1
|
Federal Agency for Scientific Organizations
|
0303-2016-0013
|
The paper presents the low-temperature nitrogen adsorption, TG, XRD, IR spectroscopy, XPS, TEM and SEM data for ruthenium promoted (0.2–1 wt.%) Сo-δAl2O3 catalysts and characteristics of the catalysts in Fischer-Tropsch synthesis after their activation under the conditions ensuring the reduction of comparable fractions of metallic cobalt. It was shown that cobalt in oxide precursors is a component of the spinel-like Со3-xAlxO4 phase containing the impurity anions СО32−, NO3−, ОН−, and NO in promoted samples, which belong to the thermolysis product of the Ru precursor. Average sizes of Со3-xAlxO4 crystallites are in a range of 5–10 nm. As ruthenium content in the catalyst increases upon reduction, the temperature of metallic phase formation decreases substantially (by more than 150 °C). After the reduction, selectivity of promoted catalysts for α-olefins and high-molecular hydrocarbons was higher in comparison with unpromoted catalysts, without a noticeable decrease in catalytic activity. Therewith, in 0.5-1.0 wt.% catalysts, a part of ruthenium forms individual ultradispersed metallic particles ca. 1 nm in size that are located on the surface of oxide support and are not active in Fischer-Tropsch synthesis. The oxide layer decorating the surface of metallic cobalt particles is also strongly enriched with ruthenium. In the 0.2 wt.% catalyst, the major part of ruthenium resides in metallic cobalt particles. Although the ruthenium-cobalt alloy segregates with enrichment of the surface with cobalt, the presence of ruthenium in the metallic particles and probably in the decorating oxide layer exerts a considerable effect on selectivity of the catalysts.