A Comprehensive Review on Red Mud‐Based Catalysts: Modification Methods and Applications in Thermal‐ and Photocatalysis

Abstract

Red mud (RM), the waste of the Bayer process for aluminum production, is mostly stored in landfill areas, creating serious environmental and economic problems. It offers substantial potential for catalytic applications, mostly because of its cost efficiency and rich chemical composition, including the oxides of Fe, Si, Al, and Ti. Using RM as a catalyst not only contributes to environmental protection but also offers economic advantages as it can potentially reduce the reliance on expensive noble metals typically used in solid catalyst formulations. RM is predominantly used in thermal‐ and photo‐catalysis, serving as a bulk catalyst, support material, promoter, additive, or as a host material for heterojunction catalysts. Prior to use, RM is generally modified to enhance its textural properties and tailor its composition. This review provides a comprehensive analysis on the utilization of RM in catalytic applications. The structural changes resulting from various pretreatments and their impact on catalytic properties are discussed. Key thermal‐ and photo‐catalytic reactions involving the use of RM‐based catalysts are presented to highlight their industrial and environmental potential. Potential pathways for further optimization of RM‐based catalysts are also proposed, offering a broad perspective on future directions in the field.