A Renewable Solar‐Thermal Pathway for Complete Red Mud Upcycling

ABSTRACT

Red mud, the highly alkaline by‐product of the Bayer alumina process, creates a major environmental challenge. Global annual production exceeds 180 million tons, with accumulated stockpiles nearing 4 billion tons, posing significant disposal risks. This perspective outlines an innovative multistage pathway for complete valorization of this residue via a circular economy model. It integrates: (1) neutralization and chemical activation of red mud; (2) recovery of critical trace metals (e.g., Sc, V, and rare earth elements [REEs]) to reduce toxicity and generate economic value; and (3) hydrothermal conversion of the remaining aluminosilicate residue into high‐performance ZSM‐5 zeolite. Central to this sustainable process is concentrated solar power (CSP), which provides the high‐temperature thermal energy for calcination and synthesis, decoupling it from fossil fuels. The resulting ZSM‐5 zeolite applies directly in catalysis, construction, and environmental remediation, closing the material loop.