Research progress on resource utilization of phosphogypsum

Abstract Abstract: Phosphogypsum is a by-product generated during wet phosphoric acid production. The massive accumulation of phosphogypsum has caused serious environmental issues, making the development of innovative and comprehensive utilization methods critically important. Both phosphogypsum and natural gypsum primarily consist of CaSO4·2H2O and treated phosphogypsum can be converted into valuable gypsum resources for various applications. This Review provides an overview of the impurities in phosphogypsum and elaborates on the common methods for its pretreatment, highlighting that the key challenge in the resource utilization of phosphogypsum lies in reducing and removing its impurity content. Phosphogypsum pretreatment serves as the foundation, and the diversification of pathways for its resource utilization will be an inevitable trend. As indicated in previous studies, phosphogypsum can be combined with various materials through a carefully designed mix-and-match strategy, resulting in significant improvements in engineering properties and expanding its range of applications. However, achieving high-value utilization of phosphogypsum remains a major challenge. The “synergistic effect of solid waste” and “treating waste with waste” will be the new trends in the high-value development of phosphogypsum. This Review focuses on the modification method of phosphogypsum and the direction of resource utilization to provide a reference for promoting the high-value development of phosphogypsum.