Preparation of diatomite-based SA@ZIF-8 composite microspheres by electrostatic spray method and its adsorption performance for Cu(II)

Diatomite (DE)-based sodium alginate (SA) loaded ZIF-8 composite microspheres were prepared by high-voltage electrostatic spray technology. SA/DE microspheres were prepared by SA and acid-base-regulated silica sol solution. Ultra-small ZIF-8 was grown on SA/DE microspheres by in-situ synthesis method to obtain ultra-high specific surface area composite microspheres. The morphology and particle size of the composite microspheres were analyzed by SEM, and characterized by FT-IR, XRD and TGA. The optimum adsorption efficiency were achieved by a series of conditions optimization. The adsorption of Cu(II) by SA/DE@ZIF-8 conforms to the Langmuir adsorption model, and the theoretical maximum adsorption capacity is 599.07 mg/g. In summary, this study opens up a new strategy for the design of efficient and easily recycled ZIF-8 composite microspheres for water treatment.