Magnetically recoverable swellable magnetite/SOMS hybrid nanocomposites for rapid adsorption of organic dyes from water

Hybrid magnetic adsorbents based on magnetite nanoparticles and Swellable Organically Modified Silica (Mag-SOMS) are reported for the first time to address the limited recoverability of powdered adsorbents from aqueous media. The materials are synthesised by combining magnetite nanoparticles obtained via different co-precipitation routes (MagA and MagB) with a SOMS matrix prepared through a sol–gel process. Structural, spectroscopic, textural, and magnetic characterisation confirms that the magnetite phase preserves its crystalline structure and magnetic properties after integration into the SOMS framework, though the hybrid materials exhibit different morphologies depending on the synthesis conditions. Both MagA-SOMS and MagB-SOMS systems remove more than 99% (1.91 mg g−1 adsorbed) of Rhodamine B from water within 10 minutes. The materials can be easily recovered by magnetic separation and being regenerable, can be reused for several adsorption cycles without losing their performances, highlighting their potential for water treatment applications.