Preliminary studies on hydrated cement for its reuse in geopolymers

The carbonation of hydrated ordinary Portland cement (OPC) allows the transformation of hydrated calcium aluminates and silicates into calcium carbonate and amorphous silica/ alumina. These carbonated materials are appropriate to being used as inorganic precursors for alkaline activation. The use of...

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Autores:
Segura Sierpes, Yasna
Borrachero Rosado, María Victoria
Monzó Balbuena, José María
Payá Bernabeu, Jordi
Tipo de recurso:
Article of journal
Fecha de publicación:
2016
Institución:
Universidad Nacional de Colombia
Repositorio:
Universidad Nacional de Colombia
Idioma:
spa
OAI Identifier:
oai:repositorio.unal.edu.co:unal/60567
Acceso en línea:
https://repositorio.unal.edu.co/handle/unal/60567
http://bdigital.unal.edu.co/58899/
Palabra clave:
62 Ingeniería y operaciones afines / Engineering
Alkali activation
carbonation
geopolymer
hydrated cement
mechanical strength
microstructure
waste.
Rights
openAccess
License
Atribución-NoComercial 4.0 Internacional
Description
Summary:The carbonation of hydrated ordinary Portland cement (OPC) allows the transformation of hydrated calcium aluminates and silicates into calcium carbonate and amorphous silica/ alumina. These carbonated materials are appropriate to being used as inorganic precursors for alkaline activation. The use of sodium silicate and hydroxide solutions enables the production of cementitious gels. Two ways of carbonation of hydrated cement were studied: in a dry environment, where relative humidity did not exceed 70% and in an aqueous medium at a temperature of 5 ± 1 ° C. Both materials were micro-structurally characterised and they have been used for the manufacturing of geopolymeric mortars. These mortars reached mechanical strength between 10 and 20 MPa, depending on the activating solution, the water/binder ratio and curing time/temperature. These results show the feasibility of reusing hydrated cement contained in construction and demolition wastes.