## 1 Introduction  
The wet phosphoric acid (WPA) process is the predominant industrial method for producing phosphoric acid (H\({}_{3}\)PO\({}_{4}\)) from phosphate ore using sulfuric acid [1, 2, 3]. The main chemical reaction can be expressed as:  
\[\mathrm{Ca}_{5}\mathrm{F}(\mathrm{PO}_{4})_{3}+\mathrm{5H}_{2}\mathrm{SO}_{4}+ \mathrm{nH}_{2}\mathrm{O}\to 3\mathrm{H}_{3}\mathrm{PO}_{4}+\mathrm{5 CaSO}_{4} \cdot\mathrm{nH}_{2}\mathrm{O}+\mathrm{HF}\]  
Phosphogypsum (PG) is the primary by-product of phosphoric acid production [2, 4], with approximately 4.55 tons of PG generated for every ton of P\({}_{2}\)O\({}_{5}\) produced (calculated as P\({}_{2}\)O\({}_{5}\)) [5, 6]. Globally, the annual production of PG reaches around 300 million metric tons [7]. However, the comprehensive utilization rate of PG remains alarmingly low at only 15%, with the remaining 85% being landfilled, stockpiled, or discarded [8]. This practice not only occupies vast land areas but also poses significant environmental risks [9]. The environmental threat is primarily driven by the presence of soluble phosphates and fluorides, which can leach into soil and water, causing severe ecological damage [10; 11]. Consequently, the low utilization rate and environmental hazards highlight the urgent need for effective strategies to stabilize these impurities and enable the sustainable use of PG [12; 13]. Various efforts have explored PG's application in soil conditioning [14], new materials [15; 16], and construction [17; 18]. While these approaches offer some mitigation, the actual demand for PG in these areas is insufficient to achieve large-scale utilization. Moreover, impurities in PG, such as heavy gold ions [19], fluoride [11; 20], phosphoric acid [21], and radioactive elements [7; 16; 22], are the main reasons limiting its application. Particularly, phosphorus and fluorine impurities directly affect the compressive strength and setting time of PG-based cement materials [23; 24; 25]. Therefore, the effective stabilization of these harmful substances is key to solving the environmental pollution problems associated with PG and improving its utilization rate. The current PG pretreatment methods, such as water washing, are widely used [25; 26; 27]. However, these techniques are resource-intensive, requiring large amounts of water and energy, further exacerbating water scarcity issues. Additionally, water washing generates significant wastewater, posing risks of secondary pollution if not adequately treated. Moreover, these methods involve complex processes, high equipment costs, and significant labor requirements, reducing their economic viability [28]. In contrast, dry treatment techniques present several advantages, including resource conservation, cost reductions, and the avoidance of wastewater generation [29]. These methods also simplify the operational process, lowering the equipment and labor costs. Given their efficiency, environmental compatibility, and economic feasibility, dry reaction methods show significant potential for large-scale PG treatment, offering a sustainable and cost-effective solution for the utilization of this industrial by-product. Phosphorus and fluorine impurities in PG can be effectively stabilized through advanced curing technologies [29; 30; 31]. These techniques immobilize impurities within specific crystalline structures or chemical compounds [32; 33], significantly reducing their mobility and solubility. As a result, curing treatments enhance the environmental safety and utilization potential of PG. curing technology has been recognized as an efficient, rapid, and cost-effective method for managing phosphorus and fluorine impurities [34]. By encapsulating these impurities in dense matrices or converting them into stable, insoluble compounds, the risk of leaching is substantially mitigated. Recent advancements have shown that incorporating specific materials can significantly improve the curing performance [35; 36; 37].