Dai Yimo, Zeng Heping, Duan Li, Yang Jie, Ma Liping, Huang Bing
Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China.
Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, 650093, Yunnan, China.
Environ Res. 2025 Jul 21;285(Pt 2):122403. doi: 10.1016/j.envres.2025.122403.
Heavy metal pollution in soil has been an urgent issue in recent decades. However, traditional stabilization technology is inefficient or costly. In the meantime, the utilization of phosphogypsum is inadequate to cope with a vast annual production in China, resulting in its large-scale stockpiling, which causes environmental pollution and economic detriment. This work provides a new approach for preparing a calcium polysulfide solution to remediate copper-contaminated soil with phosphogypsum as the calcium and sulfur source. Data for this study were collected through simulation calculations, tube furnace experiments, and Cu-contaminated soil treatment experiments. The results showed the optimal decomposition conditions with the best solidification effect, and the highest solidified rate of copper·ions in soil reached 97 %. Phosphogypsum was reduced to CaS and CaO, which synthesize polysulfide by reacting with S. Cu was reduced by phosphogypsum-based polysulfide, meanwhile, covalent bonds are formed between Cu and S. This work will generate fresh insight into the resource recycling of phosphogypsum, and solve environmental issues that industry waste and heavy metal pollution in the meantime.
近几十年来，土壤中的重金属污染一直是一个紧迫的问题。然而，传统的稳定化技术效率低下或成本高昂。与此同时，磷石膏的利用率不足以应对中国每年大量的产量，导致其大规模堆存，造成环境污染和经济损失。这项工作提供了一种新的方法，以磷石膏为钙源和硫源制备多硫化钙溶液来修复铜污染土壤。本研究的数据通过模拟计算、管式炉实验和铜污染土壤处理实验收集。结果表明了具有最佳固化效果的最佳分解条件，土壤中铜离子的最高固化率达到97%。磷石膏被还原为CaS和CaO，它们与S反应合成多硫化物。铜被磷石膏基多硫化物还原，同时，铜和硫之间形成共价键。这项工作将为磷石膏的资源回收带来新的见解，同时解决工业废物和重金属污染的环境问题。
