Superparamagnetic nanocomposite microparticles (NCMPs) modified with various layered double hydroxides (LDHs) (MgFe, MgAl and their Zr-doped equivalents) were investigated for phosphorus (P) removal. Screening of optimum composition was performed based on the P removal performance of NCMP@LDH particles as well as their magnetic separability in a flow-through column as a function of NCMP content (100–1000 mg) and stability as a function of LDH content (20–100%). The results showed that except for NCMP@MgFe-Zr, all the other particles exhibited a partial dissolution of LDH components at each of the examined LDH contents. However, NCMP@MgFe-Zr showed no dissolution up to a LDH content of 60% at all, whereas a partial dissolution occurred at a LDH content of 80 and 100%. Results of magnetic separability test revealed that the NCMP@MgFe-Zr composed of 500 mg magnetic particle (NCMP) and 60% LDH was separated from the solution with a separation efficiency of 96.9%, while lower NCMP contents resulted in lower separation efficiencies. P removal efficiency and specific removal capacity of the NCMP@MgFe-Zr with the optimized composition was found to be 18.5% and 53.1 mg/g, respectively. The crystal structure, chemical composition, surface morphology, crystallite size and particle size distribution, functional groups and magnetic properties of the NCMP and NCMP@MgFe-Zr particles were confirmed by various characterization analysis. The observed results clearly demonstrates that the NCMP@MgFe-Zr with the optimized composition remained stable during the removal experiments and enabled the removal of P under the conditions of acidic pH and relatively high P concentration without LDH dissolution.

研究了用各种层状双氢氧化物 (LDH)（MgFe、MgAl 和它们的 Zr 掺杂等效物）修饰的超顺磁性纳米复合微粒 (NCMP) 去除磷 (P) 的作用。基于 NCMP@LDH 颗粒的除磷性能以及它们在流通柱中的磁分离性作为 NCMP 含量（100-1000 mg）的函数和作为 LDH 含量函数的稳定性来筛选最佳组成（ 20–100%）。结果表明，除 NCMP@MgFe-Zr 外，所有其他颗粒在每个检测的 LDH 含量下都表现出 LDH 组分的部分溶解。然而，NCMP@MgFe-Zr 在 LDH 含量为 60% 时完全没有溶解，而在 LDH 含量为 80% 和 100% 时发生部分溶解。磁分离性测试结果表明，由500 mg磁性颗粒（NCMP）和60% LDH组成的NCMP@MgFe-Zr从溶液中分离出来，分离效率为96.9%，而NCMP含量越低，分离效率就越低。发现具有优化组成的 NCMP@MgFe-Zr 的 P 去除效率和比去除能力分别为 18.5% 和 53.1 mg/g。通过各种表征分析证实了NCMP和NCMP@MgFe-Zr颗粒的晶体结构、化学成分、表面形貌、微晶尺寸和粒度分布、官能团和磁性。