Magnetic properties and adsorptive performance of manganese–zinc ferrites/activated carbon nanocomposites

•Mn0.5Zn0.5Fe2O4 (MZF) as few as possible was implanted into activated carbon (AC) for the higher surface area.•Sample-5 possessed the high specific surface area (1129 m2 g−1) and the suitable Ms (3.96 emu g−1).•Methylene blue was adsorbed almost completely by MZF/AC nanocomposites in 30 min.•MZF/AC nanocomposites were separated easily from solution by magnetic separation technique.

Owing to the unique microstructure and high specific surface area, activated carbon (AC) could act as an excellent adsorbent for wastewater treatment and good carrier for functional materials. In this paper, manganese–zinc ferrites (Mn0.5Zn0.5Fe2O4: MZF) were anchored into AC by hydrothermal method, resulting in the excellent magnetic response for AC nanocomposites in wastewater treatment. All results demonstrated the magnetic nanoparticles presented a spinel phase structure and existed in the pores of AC. The saturation magnetization (Ms) of MZF/AC nanocomposites increased with the ferrites content, while the pore volume and specific surface area declined. The Sample-5 possessed the specific surface area of 1129 m2 g−1 (close to 1243 m2 g−1 of AC) and Ms of 3.96 emu g−1. Furthermore, the adsorptive performance for organic dyes was studied and 99% methylene blue was adsorbed in 30 min. The magnetic AC nanocomposites could be separated easily from solution by magnetic separation technique.

Graphical abstractThe Sample-5 presented both good magnetic response and high BET surface area up to 1129 m2 g−1 (close to AC of 1243 m2 g−1), which could be separated completely for about 60 s. MZF/AC nanocomposites (Sample-3, 4, 5) in our work could be used as the magnetic absorbents, which could be separated easily by an outer magnet after the MB adsorption.Figure optionsDownload full-size imageDownload as PowerPoint slide