English   español  
Por favor, use este identificador para citar o enlazar a este item: http://hdl.handle.net/10261/20146
Compartir / Impacto:
Add this article to your Mendeley library MendeleyBASE
Citado 63 veces en Web of Knowledge®  |  Ver citas en Google académico
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL

Alkali activation of metakaolins: parameters affecting mechanical, structural and microstructural properties

AutorGranizo, M. L.; Blanco-Varela, María Teresa; Martínez-Ramírez, S.
Fecha de publicación23-ene-2007
CitaciónJournal of Materials Science 42(9): 2934-2943 (2007)
ResumenThe composition, structure and properties of the reaction product resulting from the alkali activation of metakaolin (MK) are directly impacted by the specific surface and composition of the initial kaolin and the type, concentration and relative amount of alkali activator used. This study aimed to analyze the effect of these parameters on the flexural strength, degree of reaction, porosity and chemical and mineralogical composition of alkali-activated metakaolin pastes. Two types of metakaolin with different specific surfaces were activated under hydrothermal conditions (85 °C, 2 h) using solutions consisting of waterglass and Na(OH) as activators (Na concentrations = 6, 8, 10, 12, 15, 18, 20 M) and two metakaolin/solution ratios. Regression analysis was used to quantify the effect of the parameters tested (activator concentration and MK/solution ratio) on flexural strength. Mathematical models were likewise built to relate the degree of reaction and amount of sodium fixed in the polymer structure to the synthesis parameters. According to 29Si and 27Al MAS NMR, XRD, FTIR, DTA/TG data and chemical analysis, the material obtained by activating two MKs with waterglass plus NaOH was an amorphous hydrated sodium aluminosilicate in which a Q4 Si (3Al) type three-dimensional structure predominated, i.e., a structure where three Al atoms are connected to SiO4 tetrahedra. The alkaline ions in the structure maintain the electrical balance. The general formula obtained for this inorganic polymer was Na2O·3SiO2·Al2O3·3H2O.
DescripciónPublicación en versión impresa: mayo de 2007
Versión del editorhttp://dx.doi.org/10.1007/s10853-006-0565-y
ISSN0022-2461 (Print)
1573-4803 (Online)
Aparece en las colecciones: (IETCC) Artículos
Ficheros en este ítem:
No hay ficheros asociados a este ítem.
Mostrar el registro completo

NOTA: Los ítems de Digital.CSIC están protegidos por copyright, con todos los derechos reservados, a menos que se indique lo contrario.