Effect of the sol-gel route on the textural characteristics of silica imprinted with Rhodamine B.
J Sep Sci
; 37(7): 868-75, 2014 Apr.
Article
em En
| MEDLINE
| ID: mdl-24478149
A series of silica xerogels that support Rhodamine B as a template were synthesized using distinct sol-gel routes, namely, acid-catalyzed routes, a base-catalyzed route, acid-catalyzed with base-catalyzed (two steps) hydrolytic routes, and a FeCl3 -catalyzed nonhydrolytic route. The extraction methods (thermal, Soxhlet, water washing, and ultrasound) were also evaluated. The resulting xerogels were characterized through porosimetry using nitrogen adsorption/desorption. The samples were further analyzed through small-angle X-ray scattering, Fourier transform infrared spectroscopy, and SEM. The preparation route affected the materials' textural properties. Extraction was optimized using acid and two-step routes. The acid route from Rhodamine B to Rhodamine 6G generated the highest selectivity factor (2.5). The nonhydrolytic route produced the best imprinting factor. Competitive adsorption was also used, from which the approximate imprinting factor was 2. The cavity shape generated during the production of the imprinted silica dictates the adsorption behavior, not the magnitude of the surface area.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Rodaminas
/
Dióxido de Silício
/
Impressão Molecular
/
Géis
Idioma:
En
Revista:
J Sep Sci
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Alemanha