Revisiting phosphogypsum utilization: Technological bottlenecks, emerging solutions, and the path toward commercial viability

Global stockpiles of phosphogypsum (PG) have reached 7 billion tons, yet its resource utilization rate remains below 15%, making its environmental management and reuse a worldwide challenge. This review identifies the efficient removal of impurities—such as phosphorus, fluorine, heavy metals, and radionuclides—as the key bottleneck to its utilization. It examines the principles and limitations of current pre-treatment methods (physical, chemical, and thermal) and evaluates utilization pathways in construction, soil amendment, ecological restoration, chemical recovery, and CO 2 fixation. While these approaches are diversifying, they often face constraints like high cost, low product value, limited long-term assessment, and poor economic viability. Future efforts should prioritize high-value, large-scale applications—like mineral carbonation for CO 2 sequestration and rare earth extraction—based on advanced impurity separation. A life-cycle assessment (LCA) framework is essential to align PG management with circular economy goals (waste assimilation, emission reduction, resource recovery). Policy interventions—integrating regulatory mandates, targeted subsidies, and market-driven mechanisms—are critical to foster a full-chain industrial ecosystem, transforming PG from an environmental liability into a “urban mine.” This review provides a holistic reference for PG management, bridging technological innovation, sustainability assessment, and policy design to advance global resource recycling and climate resilience.