The Third-Generation Magnetic Super-Stable Mineralizer: Complete Removal and Separation of Multiple Heavy Metal...

The retrieval of used mineralizers from multiple heavy metals contaminated environments is a critical challenge that remains to be solved regarding in situ super-stable mineralization. Herein, the third-generation magnetic mineralizer represented by the M-MgAl-700 was successfully fabricated with a typical core-shell structure, strong superparamagnetism, a large specific surface area, and abundant oxygen defects. The resultant M-MgAl-700 exhibited maximum mineralization capacities of 1173.80 and 93.11 mg g^‒1 for individual Cd(II) and As(V), respectively, which markedly surpassed the majority of mineralizers reported so far. Moreover, the M-MgAl-700 can reduce the concentrations of both Cd(II) and As(V), no matter in co-polluted water or soil, to levels compliant with national standards (GB8978-1996 and GB15618-2018), highlighting its versatile utility. Detailed quasi in situ characterization and density functional theory (DFT) calculation collectively revealed the diverse removal mechanisms of topological transformation to form the CdAl-CO₃ for Cd(II) and surface adsorption via a binuclear bidentate mode for As(V), respectively. More crucially, the mineralized products with adequate magnetism allowed for highly efficient and thorough isolation from water and soil by using the magnet. This work presents the third-generation magnetic super-stable mineralizer that integrates high-capacity mineralization with rapid, facile, and complete recoverability, offering a cross-disciplinary platform for the development of advanced environmental remediation.