Geopolymer Composites-In Environmentally Friendly Aspects

In the present work, a new, low energy consumption sol-gel synthesis route has been developed for geopolymer composites. Instead of the typically published 0.1-1.0 Al/Si molar ratios, the efforts of this study concentrated on the realization of >2.5 Al/Si molar ratios in the composite systems. The higher Al molar ratio significantly improves the mechanical properties. A very important aim was also the recycling of industrial waste materials with attention to environmentally friendly requirements. The very dangerous, toxic red mud as a waste product of aluminum industrial fabrication was selected for reclamation. The structural investigation was carried out by Al-27 MAS NMR, XRD, and thermal analysis. The structural examination has unambiguously proven the composite phases in both gel and solid systems. The characterization of composites was performed with mechanical strength and water solubility measurements.

Automated summary

A new sol-gel synthesis route with low energy consumption was developed for geopolymer composites. The study focused on achieving >2.5 Al/Si molar ratios in the composites, which significantly improved the mechanical properties. The recycling of industrial waste materials, specifically the toxic red mud from aluminum fabrication, was also a key aspect. The structure of the composites was analyzed using Al-27 MAS NMR, XRD, and thermal analysis, confirming the presence of composite phases. The composites were characterized by their mechanical strength and water solubility.