From Toxic Waste to Sustainable Building: Red Mud Cementitious Composites for Environmental Remediation
This study evaluates mortar containing up to 15% red mud as a cement substitute, focusing on strength, pore structure, and hydration behaviour. The primary goal of this study is to evaluate red mud as a low-cost and effective photocatalyst for air pollutant degradation. Further the study briefly exa...
| Autores: | , , , , |
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| Tipo de recurso: | capítulo de libro |
| Fecha de publicación: | 2025 |
| País: | España |
| Institución: | Universidad de Navarra |
| Repositorio: | Dadun. Depósito Académico Digital de la Universidad de Navarra |
| Idioma: | inglés |
| OAI Identifier: | oai:dadun.unav.edu:10171/123744 |
| Acceso en línea: | https://hdl.handle.net/10171/123744 |
| Access Level: | acceso abierto |
| Palabra clave: | Photocatalytic activity NO abatement Red mud Cementitious mortars Engineering properties |
| Sumario: | This study evaluates mortar containing up to 15% red mud as a cement substitute, focusing on strength, pore structure, and hydration behaviour. The primary goal of this study is to evaluate red mud as a low-cost and effective photocatalyst for air pollutant degradation. Further the study briefly examines the photocatalytic performance of red mud-based composites coated with titanium dioxide (TiO₂) to assess whether the incorporation of red mud affects the visible light absorption characteristics of TiO₂. The findings suggest that incinerating red mud at 600ºC does not improve the pozzolanic activity of red mud. The low reactivity and lack of desirable compounds in red mud affect both strength development and pore refinement in cementitious materials, leading to decreased compressive strength and increased porosity in red mud-based mortars. Increasing red mud content led to significant strength loss, with oven-dried red mud-based samples i.e., R10-105 and R15-105 showing 20% and 44% reductions in compressive strength, while incinerated red mud-based counterparts exhibited a 20–31% decrease compared to the control. Nevertheless, incorporation of red mud into cementitious mortars yields materials with high photocatalytic efficiency for nitrogen oxides removal, achieving Class 3 performance in air purification level with over 8% NO degradation. Incorporating red mud alters the visible light absorption of TiO₂, with the TiO₂-coated R5-105-F-CI sample achieving a 26% higher NO removal under visible light compared to R5-105-F-CO. It is attributed to synergistic effects and enhanced charge separation at the Fe₂O₃/TiO₂ interface, underscoring the potential of red mud–TiO₂ composites for effective pollutant degradation. Incorporating red mud into cementitious materials enables the development of multifunctional building products that support both structural and environmental functions. Particularly suitable for non-structural applications like red mud-based tiles, this approach aligns with sustainable construction by promoting circular economy principles and offering potential for environmental remediation through photocatalytic properties. |
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