Synthesis of a composite Fe3O4@SiO2/poly(SMA-co-BA-co-BZMA-co-DMC) and evaluation of its oil-water separation performance

To obtain a demulsification material with convenient recovery, high oil-water separation capacity, and excellent reusability, Fe3O4@SiO2 core-shell particles and hydrophilic DMC were introduced into the acrylic ester-based polymer system to prepare a magnetic amphiphilic composite demulsifier, Fe3O4@SiO2/poly(SMA-co-BA-co-BZMA-co-DMC) (Fe3O4@SiO2/PAMCs-P). The molecular structure of Fe3O4@SiO2/PAMCs-P was characterized using FT-IR and XPS, while the morphology was observed using SEM. Additionally, the effects of TEOS, Fe3O4@SiO2 core-shell particles, and DMC dosage on the demulsification performance of the composites were discussed in detail. Fe3O4@SiO2/PAMCs-P exhibited excellent demulsification, oil-water separation, and reusability properties for CTAB-toluene emulsions. Under magnetic field conditions, Fe3O4@SiO2/PAMCs-P achieved saturated separation within 2 h with a separation efficiency of 97.9%. After five consecutive separations, the separation efficiency decreased to 39.1%, but it could be restored to 91.5% of the initial separation efficiency after desorption. These results indicate that Fe3O4@SiO2/PAMCs-P has valuable application potential in emulsified wastewater treatment.