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Magnetic polymeric matrixces were synthesized from glycidyl methacrylate, N,N′-methylenebis(acrylamide) (MBA), and nanomagnetite particles. The obtained polymers were modified by ethylenediamine (DA) and diethylenetriamine (TA) to produce two amino-magnetic resins named R-DA and R-TA. The recovery of Th(IV) ions from their aqueous solutions by R-DA and R-TA were studied in the pH range 1−4. Maximum adsorption capacity values of 60 and 84 mg/g of Th(IV) ions on R-DA and R-TA, respectively, were obtained at pH 3.5 and 293 K. At a solid/liquid ratio (S/L) of 2 g/L, recovery efficiency values of 86 and 95% were achieved from initial thorium ion concentration of 100 mg/L using R-DA and R-TA, respectively. Adsorption isotherms and kinetic and thermodynamic parameters of the adsorption process were obtained and analyzed. Regeneration of the resins was tested by eluting the loaded Th(IV) ions on the spent resins using 0.2 M HNO 3 followed by washing with dilute NaOH.

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We report the selective engineering of hybrid organic mesoporous silica monolith adsorbents for the recovery of silver (Ag) ions from e‐waste samples. The AgI multithiolated adsorbent scales were synthesized through dense and continuous surface modifications of hierarchically ordered mesoporous (HOM) monoliths by active organic moieties. Captured subsets were created on the monolithic surfaces and in the orderly pore cavities for suitable AgI trapping. In addition, HOM monolithic carriers, with unique surface dominants, micrometer‐sized particles, high surface‐area/pore‐volume ratios, and uniform groove‐like cage cavities, form neat rooms for target ions. The decoration and depression of the extraordinary micrometer‐sized surface monoliths and the orderly neat grooves enable the adsorption of large quantities and well‐dispersed coverage of the multithiolated layers. These layers include sulfur‐ and nitrogen‐active sites that selectively improve AgI adsorption/trapping/capture among competitive matrices. Results indicate that the adsorption of AgI is strong at pH 6.5 and it appears to follow the Langmuir adsorption model, with a maximum capacity of 179.23 mg g–1. The hierarchical multithiolated adsorbent scales exhibit selectivity for Ag ions in the presence of coexisting cations. The retention of the organic structure and orientation along the HOM monoliths enables multiple‐use recovery, collection, and management of AgI, without altering their functionality and capacity. The results suggest that the hierarchical adsorbent scales are suitable for AgI recovery from aquatic samples.

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Magnetic amine resins composed of nanomagnetite (Fe3O4) core and glycidyl methacrylate (GMA)/N,N′-methylenebisacrylamide (MBA) shell were prepared by suspension polymerization of glycidyl methacrylate with N,N′-methylenebisacrylamide in the presence of nanomagnetite particles and immobilized with different amine ligands. These resins showed good magnetic properties and could be easily retrieved from their suspensions using an external magnetic field. Adsorption behaviors of uranium ions on the prepared resins were studied. Maximum sorption capacities of uranium ions on R-1 and R-2 were found to be 92 and 158 mg/g. Uranium was extracted successfully from three granite samples collected from Gabal Gattar pluton, North Eastern Desert, Egypt. The studied resins showed good durability and regeneration using HNO3.