KIT | KIT-Bibliothek | Impressum | Datenschutz

Influence of lime, calcium silicate and portlandite on alkali activation of calcined common clays

Dathe, Felix; Strelnikova, Vera; Werling, Nadja; Emmerich, Katja; Dehn, Frank

Abstract:

The application of calcite rich common clays has marked impact on the formation of alkali-activated binders. Experiments have shown that the carbonate decomposition can be well controlled via the calcination procedure, whereby the majority of the decomposition and the subsequent CO$_{2}$ release occurs above the calcination temperature of 750 ​°C. The decarbonation of the calcite can mostly be separated from the dehydroxylation of the layered silicates. Depending on the composition of the raw clay material, the CaCO$_{3}$ decomposition leads either to the formation of lime or other Ca rich minerals. The mechanical properties of the alkali-activated binders were investigated and despite the very low amounts of layered silicates of the clay raw materials and the high content of unreactive minerals, compressive strengths of above 20 ​MPa of the mortars could be obtained. The presence of lime in calcined clays up to an adequate amount has a positive effect on post-solidification and the carbonation resistance of the mortars.


Verlagsausgabe §
DOI: 10.5445/IR/1000136940
Veröffentlicht am 06.09.2021
Originalveröffentlichung
DOI: 10.1016/j.oceram.2021.100152
Scopus
Zitationen: 5
Dimensions
Zitationen: 5
Cover der Publikation
Zugehörige Institution(en) am KIT Kompetenzzentrum für Materialfeuchte (CMM)
Publikationstyp Zeitschriftenaufsatz
Publikationsjahr 2021
Sprache Englisch
Identifikator ISSN: 2666-5395
KITopen-ID: 1000136940
Erschienen in Open Ceramics
Verlag Elsevier
Band 7
Seiten Art.-Nr.: 100152
Schlagwörter Alkali activation; Geopolymers; Alkali-activated binders; Common clays; Calcium oxide
Nachgewiesen in Scopus
Dimensions
KIT – Die Forschungsuniversität in der Helmholtz-Gemeinschaft
KITopen Landing Page