A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Waste-derived activators for alkali-activated materials: A review
Abstract Alkali-activated materials (AAMs) are increasingly attracting attention as a promising sustainable alternative to Portland cement-based materials. This study presents the key advancements in the synthesis of alternative sodium silicate activators using silica-rich waste resources, such as rice husk ash, waste glass, nanosilica and microsilica. Different silicate extraction methods, including fusion, hydrothermal, and thermochemical processes were compared, and the roles of various parameters on the silica dissolution rate were deliberated. In addition, the efficiency controlling factors of the synthesized activators were rigorously reviewed using the compressive strength, setting time, and microstructural characteristics of the resulting AAMs. The extraction of silica was shown to be effective using hydrothermal and thermochemical processes. Moreover, the recent studies showed that the proper selection of the raw materials and the extraction conditions allow for maximizing the yield of silica from the silica-rich wastes. Such proper selection provides mechanical and microstructural properties of AAMs activated by the synthesized activators comparable to those from the commercially available activators.
Highlights Synthesis of alkali activators using silica-rich waste materials are reviewed. Both the raw waste material and the synthesis process play an important role in the quality of the extracted activator. Waste-derived activators can have comparable performance to the commercial activator. The synthesis process should be optimized to extract silica from waste materials. Further research required is discussed.
Waste-derived activators for alkali-activated materials: A review
Abstract Alkali-activated materials (AAMs) are increasingly attracting attention as a promising sustainable alternative to Portland cement-based materials. This study presents the key advancements in the synthesis of alternative sodium silicate activators using silica-rich waste resources, such as rice husk ash, waste glass, nanosilica and microsilica. Different silicate extraction methods, including fusion, hydrothermal, and thermochemical processes were compared, and the roles of various parameters on the silica dissolution rate were deliberated. In addition, the efficiency controlling factors of the synthesized activators were rigorously reviewed using the compressive strength, setting time, and microstructural characteristics of the resulting AAMs. The extraction of silica was shown to be effective using hydrothermal and thermochemical processes. Moreover, the recent studies showed that the proper selection of the raw materials and the extraction conditions allow for maximizing the yield of silica from the silica-rich wastes. Such proper selection provides mechanical and microstructural properties of AAMs activated by the synthesized activators comparable to those from the commercially available activators.
Highlights Synthesis of alkali activators using silica-rich waste materials are reviewed. Both the raw waste material and the synthesis process play an important role in the quality of the extracted activator. Waste-derived activators can have comparable performance to the commercial activator. The synthesis process should be optimized to extract silica from waste materials. Further research required is discussed.
Waste-derived activators for alkali-activated materials: A review
Alnahhal, Mohammed Fouad (author) / Kim, Taehwan (author) / Hajimohammadi, Ailar (author)
2021-02-08
Article (Journal)
Electronic Resource
English