Mesoporous Aerogel-Like Al-Si Oxides Obtained via Supercritical Antisolvent Precipitation of Alumina and Silica Sols
Full article
| Common |
Language:
Английский,
Genre:
Full article,
Status:
Published,
Source type:
Original
|
| Journal |
The Journal of Supercritical Fluids
ISSN: 0896-8446
, E-ISSN: 1872-8162
|
| Output data |
Year: 2019,
Volume: 149,
Pages: 110-119
Pages count
: 10
DOI:
10.1016/j.supflu.2019.03.014
|
| Tags |
Alumina-silica mesoporous alumina; supercritical antisolvent; sols; acidity; SAS |
| Authors |
Nesterov Nikolai S.
1
,
Shalygin Anton S.
1
,
Pakharukova Vera P.
1
,
Glazneva Tatyana S.
1,2
,
Martyanov Oleg N.
1,2
|
| Affiliations |
| 1 |
Boreskov Institute of Catalysis, Lavrentieva Ave., 5, Novosibirsk, 630090, Russia
|
| 2 |
Novosibirsk State University, Pirogova str., 2, Novosibirsk, 630090, Russia
|
|
Funding (2)
|
1
|
Federal Agency for Scientific Organizations
|
0303-2016-0001
|
|
2
|
Russian Foundation for Basic Research
|
18-29-06022
|
A method of alumina and silica sols precipitation in supercritical CO2 has been developed for the first time to prepare alumina and silica doped alumina. The silicon content of samples is varied within the range from 0 to 30 mol. %. The approach suggested can be considered as a development of supercritical antisolvent (SAS) method that is widely used to prepare powders from solutions but not sols. The alumina and silicon-doped alumina obtained are shown to be mesoporous materials with narrow size distribution in the range of 3-5 nm. The high-temperature treatment of the sample containing 10 mol. % of Si results in the formation of γ-Al2O3 phase followed by its transition into the δ-Al2O3 phase at 1200 °C without α-Al2O3 phase formation. It is demonstrated that the gradual introduction of silica into the alumina allows one to fine-tune the strength and amount of acid sites existing in oxides.