In-situ formation of geopolymer foams through addition of silica fume: Preparation and sinterability
Autor: | R.M. Khattab, Ayman A. Abdel-Shafi, S.E. Abo Sawan, Mahmoud F. Zawrah |
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Rok vydání: | 2020 |
Předmět: |
Materials science
Silicon Silica fume technology industry and agriculture chemistry.chemical_element Sintering 02 engineering and technology equipment and supplies 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences 0104 chemical sciences Geopolymer Compressive strength chemistry visual_art visual_art.visual_art_medium General Materials Science Ceramic Composite material 0210 nano-technology Porosity Metakaolin |
Zdroj: | Materials Chemistry and Physics. 239:121998 |
ISSN: | 0254-0584 |
Popis: | Recently, the production of clean binding materials without energy consumption and CO2 emission has paid a great attention. In-situ formation of geopolymer foams through addition of silica-fume waste is the main goal of the present study. Moreover, an attempt to study the effect sintering temperature on the prepared geopolymer foams was also conducted. Through geopolymer formation, the silicon impurity in silica fume reacted with the alkali activator and produced hydrogen gas which entrapped inside the structures generating highly porous foams. Geopolymer foams were prepared by alkali activation of metakaolin with partially replacement by 2.5, 5 and 7.5 mass-% silica fume. To study the effect of temperature or sinterability, the prepared geopolymer foams were sintered at 800, 1000 and 1200 °C. Both dried and sintered geopolymers were subjected for assessment by various tools. The physical, microstructural and mechanical properties were investigated. The results revealed that porosity percentage of dried and sintered geopolymers increased with increasing the amount of added silica fume and decreased with increasing sintering temperature. On the other hand, the compressive strength was opposite to the porosity trend. Generally, the best results were for the geopolymer that contains 5% silica fume. The optimum sintering temperature to produce sintered ceramics having good properties was 1000 °C. |
Databáze: | OpenAIRE |
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