https://doi.org/10.1140/epjst/e2015-02494-7
Regular Article
Use of silicon carbide sludge to form porous alkali-activated materials for insulating application
1 Laboratory of Civil and Environmental Engineering, INSA Lyon, 12 avenue des Arts, 69621 Villeurbanne, France
2 Limoges University, GRESE EA 4330, 123 avenue Albert Thomas, 87060 Limoges Cedex, France
3 European Ceramic Centre, Science of Ceramic Processing and Surface Treatments, Superior National School of Industrial Ceramics, 12 rue de l'Atlantis, 87068 Limoges Cedex, France
a e-mail: Sylvie.rossignol@unilim.fr
Received: 28 November 2014
Revised: 21 May 2015
Published online: 30 July 2015
One of the objectives in the field of alkali-activated materials is the development of materials having greater thermal performances than conventional construction materials such as aerated concrete. The aim of this paper is to present the possibility to obtain controlled porosity and controlled thermal properties with geopolymer materials including a waste like silicon carbide sludge. The porosity is created by the reaction of free silicon contains in silicon carbide sludge leading to the formation of hydrogen. Two possible ways are investigated to control the porosity: modification of mixture formulation and additives introduction. The first way is the most promising and allowed the formation of materials presenting the same density but various porosities, which shows that the material is adaptable to the application. The insulation properties are logically linked to the porosity and density of materials. A lower value of thermal conductivity of 0.075 W.m−1.K−1 can be reached for a material with a low density of 0.27 g.cm−3. These characteristics are really good for a mineral-based material which always displays non-negligible resistance to manipulation.
© EDP Sciences, Springer-Verlag, 2015
