Publication detail

Alkaline activation of low-reactivity ceramics: Peculiarities induced by the precursors' dual character

FOŘT, J. VEJMELKOVÁ, E. KEPPERT, M. ROVNANÍKOVÁ, P. BEZDIČKA, P. ČERNÝ, R.

Original Title

Alkaline activation of low-reactivity ceramics: Peculiarities induced by the precursors' dual character

Type

journal article in Web of Science

Language

English

Original Abstract

In the alkaline activation process, precursors with high reactivity are mostly used. If low-reactivity materials are utilized, it is necessary to take into account their dual character, i.e., that only their amorphous portion can react and the remaining crystalline part acts as microfiller. The composite character of obtained alkali-activated materials can then induce some peculiarities which are not observed for geopolymers based on high-reactivity precursors. In this paper, alkaline activation of low-reactivity ceramic grinding dust is investigated. Microstructure and phase composition of the prepared aluminosilicates are analyzed at first, and empirical geopolymer formulas in the form nM(2)O center dot pCaO center dot Al2O3 center dot xSiO(2)center dot yH(2)O are derived in dependence on activator alkalinity and curing temperature. The dependence of flexural strength upon Al/(Na+ 1/2 Ca) molar ratio calculated for the amorphous portion of the analyzed aluminosilicates is identified as the most distinct feature characterizing the links between microstructure, composition, and properties. The improvement of mechanical properties is related to the enhancement of matrix-aggregate composite effect and refinement of pore structure due to the incorporation of crystalline substances into the aluminosilicate matrix.

Keywords

Low-reactivity ceramics; Alkaline activation; Curing temperature; Composite effects

Authors

FOŘT, J.; VEJMELKOVÁ, E.; KEPPERT, M.; ROVNANÍKOVÁ, P.; BEZDIČKA, P.; ČERNÝ, R.

Released

20. 1. 2020

Publisher

ELSEVIER SCI LTD

Location

OXFORD

ISBN

0958-9465

Periodical

CEMENT & CONCRETE COMPOSITES

Year of study

105

Number

105

State

United Kingdom of Great Britain and Northern Ireland

Pages from

1

Pages to

9

Pages count

9

URL

https://reader.elsevier.com/reader/sd/pii/S0958946519312831?token=0F7264B55ABCE1CE2DCE807684B61038D13561731B4807F04C8E01BCC24400FCBA35FCE04369D90706D652C02A8596B4

BibTex

@article{BUT162706,
  author="Jan {Fořt} and Eva {Vejmelková} and Martin {Keppert} and Pavla {Rovnaníková} and Petr {Bezdička} and Robert {Černý}",
  title="Alkaline activation of low-reactivity ceramics: Peculiarities induced by the precursors' dual character",
  journal="CEMENT & CONCRETE COMPOSITES",
  year="2020",
  volume="105",
  number="105",
  pages="1--9",
  doi="10.1016/j.cemconcomp.2019.103440",
  issn="0958-9465",
  url="https://reader.elsevier.com/reader/sd/pii/S0958946519312831?token=0F7264B55ABCE1CE2DCE807684B61038D13561731B4807F04C8E01BCC24400FCBA35FCE04369D90706D652C02A8596B4"
}