Applications of red mud as an environmental remediation material: A review

Red mud is an alkaline by-product produced by alumina plants. The accumulation of red mud is becoming an increasingly serious problem with the growth of the aluminum industry. Various waste treatment methods utilizing red mud as an environmental remediation material have been developed. Red mud environmental remediation materials (RM-ERMs) are environmental remediation materials prepared by activating red mud, synergistically using red mud and other ingredients, or by extracting effective components from red mud. There are three general categories of use for RM-ERMs: for waste water purification, waste gas purification and soil remediation. As well as providing an opportunity to improve the environment through purification technologies, the highly alkaline red mud is consumed in the production of RM-ERMs. The use of RM-ERMs has been shown to be a promising strategy for the simultaneous treatment of various wastes. In this paper, the developregeneration characteristics of various red mud granularent status of RM-ERMs is described, the physical and chemical properties of red mud are introduced, and the active mechanism of RM-ERMs on target pollutants in waste water, waste gas and soil is summarized. Moreover, a discussion on the current existing problems of RM-ERMs provides important tips and suggestions for future research on RM-ERMs. [Display omitted] •The advantages and disadvantages of several activation methods of red mud are compared.•The research status of RM-ERMs is described.•The mechanism of action of RM-ERMs on target pollutants in waste water, waste gas, and soil is summarized.•The challenge of applying red mud to soil remediation is presented.•The current development problems and future research needs of RM-ERMs are pointed out.