Synthesis of Fe3O4/MnO2/Humic acid nanocomposite for strontium ion adsorption and its interferences

The magnetic nanomaterials have attracted significant attention as effective and potential adsorbents. We synthesized the Fe3O4/MnO2/HA nanocomposite as an adsorbent for strontium adsorption. The nanocomposite was synthesized by the coprecipitation method. Humic acid (HA) is used to coat nanocomposites were obtained from the compost of TPST Supit Urang Malang City, East Java, Indonesia. HA, Fe3O4 nanoparticle, and Fe3O4/MnO2/HA nanocomposites characterized by XRD, FT-IR, VSM, SEM-EDX, and BET methods. The Fe3O4/MnO2/HA has been successfully synthesized. Coating Fe3O4 nanoparticles with MnO2/HA caused the composite size to be smaller when compared to Fe3O4 nanoparticles. The ideal situation for the adsorption of Sr2+ by the nanocomposites was 0.4 g mass of adsorbent, pH 10, and contact time of 24 hours. The pseudo-second-order model is suitable for the adsorption of Sr2+ by the nanocomposite.