Kinetics of the SiO2 Aerogel Dissolution in Aqueous NaOH Solutions: Experiment and Model Full article
| Journal |
Journal of Non-Crystalline Solids
ISSN: 0022-3093 , E-ISSN: 1873-4812 |
||||
|---|---|---|---|---|---|
| Output data | Year: 1999, Volume: 260, Number: 1-2, Pages: 21-30 Pages count : 10 DOI: 10.1016/S0022-3093(99)00568-2 | ||||
| Tags | Activation energy; Aerogels; Curve fitting; Diffusion in liquids; Mathematical models; Particle size analysis; Porosity; Silica; Sodium compounds; Solutions; Thermal effects; X ray scattering | ||||
| Authors |
|
||||
| Affiliations |
|
Funding (3)
| 1 | Russian Foundation for Basic Research | 97-03-32471 |
| 2 | Siberian Branch of the Russian Academy of Sciences | |
| 3 | The Ministry of Education and Science of the Russian Federation | 3H-256-97 |
Abstract:
The paper is devoted to the study of the kinetics of silica aerogel dissolution in 0.05–0.79 M NaOH aqueous solutions at temperatures 15–56°C. The aerogel samples are prepared via common one- and two-step procedures, and differ considerably in the primary particle size. Kinetic peculiarities of the process are studied under both reaction and diffusion controlled modes and kinetic parameters are established by experimental curve fitting. The dissolution activation energy is found to be equal to 82±6 kJ/mol for all the aerogels. The dissolution kinetic curves appear to be S-shaped, so that the process rate passes through a maximum. The coincidence of SAXS and BET specific surface areas indicates that the aerogels have no closed porosity so the initial rate increase cannot be explained by the opening of closed pores. A new modification of the Iler dissolution kinetic model has been developed to describe the experimentally observed kinetic curves.
Cite:
Okunev A.G.
, Shaurman S.A.
, Danilyuk A.F.
, Aristov Y.I.
, Bergeret G.
, Renouprez A.
Kinetics of the SiO2 Aerogel Dissolution in Aqueous NaOH Solutions: Experiment and Model
Journal of Non-Crystalline Solids. 1999. V.260. N1-2. P.21-30. DOI: 10.1016/S0022-3093(99)00568-2 WOS Scopus РИНЦ ANCAN OpenAlex
Kinetics of the SiO2 Aerogel Dissolution in Aqueous NaOH Solutions: Experiment and Model
Journal of Non-Crystalline Solids. 1999. V.260. N1-2. P.21-30. DOI: 10.1016/S0022-3093(99)00568-2 WOS Scopus РИНЦ ANCAN OpenAlex
Dates:
| Submitted: | Jan 14, 1999 |
| Published online: | Nov 18, 1999 |
| Published print: | Dec 1, 1999 |
Identifiers:
| Web of science: | WOS:000083764100003 |
| Scopus: | 2-s2.0-0033342413 |
| Elibrary: | 13315623 |
| Chemical Abstracts: | 1999:754303 |
| Chemical Abstracts (print): | 132:82124 |
| OpenAlex: | W2063714344 |