Preparation of magnetic hollow ZSM-5/Ni composite spheres

This paper presents a method for the preparation of magnetic hollow ZSM-5/Ni composite spheres. ZSM-5/Ni/PS spheres were firstly synthesized by assembling ZSM-5 nanoparticles on the surfaces of Ni/PS spheres, followed by hydrothermal treatment to form a compact ZSM-5 layer. Magnetic hollow ZSM-5/Ni spheres were subsequently obtained by calcination and reduction of the ZSM-5/Ni/PS spheres. The samples were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), thermogravimetry (TG), energy dispersive X-ray spectroscopy (EDX), temperature-programmed reduction (TPR) and a vibrating sample magnetometer (VSM). A continuous ZSM-5 layer with a thickness of 400 nm was formed on the surface of Ni/PS spheres after one cycle of adsorption of ZSM-5 nanoparticles and hydrothermal treatment at 80 °C for 36 h. By changing the hydrothermal treatment time, the thickness of zeolite layer can be controlled. The hollow ZSM-5/Ni spheres inherited magnetic property from the nickel layer and their magnetization value could be adjusted by varying the thickness of the nickel layers.