The decommissioning of uranium mill tailings (UMTs) is usually accompanied by uranium (U) contamination in soil, which poses a serious threat to human health and ecological safety. In this study, a novel phosphorus-modified bamboo biochar (PBC) cross-linked Mg–Al layered double-hydroxide (LDH) composite (“PBC@LDH”) was successfully prepared by phosphate pre-impregnation and a hydrothermal method with Mg–Al LDH. Physicochemical analysis revealed that phosphorus-containing functional groups and Mg–Al LDH were grafted onto the pristine biochar (BC) matrix. Laboratory-scale incubation and column leaching experiments were performed on the prepared BC, PBC, and PBC@LDH. The results showed that, at a dosage of 10%, the PBC@LDH composite had a commendable ability to immobilize U in soil. After 40 days of incubation with the stabilizer, the more mobile U was converted into immobilized species. Furthermore, during a column leaching experiment with simulated acid rain, the cumulative loss and leaching efficiency of U were remarkably reduced by PBC@LDH treatment compared with the control, reaching 53% and 54%, respectively. Surface complexation, co-precipitation, and reduction described the adsorption and immobilization mechanisms. In conclusion, this research demonstrates that the PBC@LDH composite offers a potentially effective amendment for the remediation of U contaminated soil.

铀厂尾矿（UMT）的退役通常伴随着土壤中的铀（U）污染，这对人类健康和生态安全构成了严重威胁。在这项研究中，成功​​地通过磷酸盐预浸渍和水热法用Mg-Pb制备了一种新型的磷改性竹生物炭（PBC）交联的Mg-Al层状双氢氧化物（LDH）复合材料（“ PBC @ LDH”）。 Al LDH。理化分析表明，含磷官能团和Mg-Al LDH接枝到了原始生物炭（BC）基质上。在制备的BC，PBC和PBC @ LDH上进行了实验室规模的孵育和柱浸实验。结果表明，在10％的剂量下，PBC @ LDH复合材料具有固定的将U固定在土壤中的能力。与稳定剂一起温育40天后，流动性越强的U被转化为固定化的物种。此外，在模拟酸雨的柱浸试验中，与对照相比，PBC @ LDH处理显着降低了U的累积损失和浸出效率，分别达到了53％和54％。表面络合，共沉淀和还原描述了吸附和固定化机理。总之，这项研究表明，PBC @ LDH复合材料为U污染土壤的修复提供了潜在的有效修正。共沉淀和还原描述了吸附和固定化机理。总之，这项研究表明，PBC @ LDH复合材料为U污染土壤的修复提供了潜在的有效修正。共沉淀和还原描述了吸附和固定化机理。总之，这项研究表明，PBC @ LDH复合材料为U污染土壤的修复提供了潜在的有效修正。