Synthesis of zeolite/magnetite nanocomposite and a fast experimental determination of its specific surface area

Abstract

In the present work, the clinoptilolite was magnetized by magnetite nano-powder synthesized by chemical co-precipitation route. The clinoptilolite/magnetite nanocomposites were prepared with different weight ratios of 7 : 1, 5 : 1, 3 : 1 and 1 : 1 using FeCl3 · 6H2O and FeCl2 · 4H2O in an aqueous phase under the ambient condition. The nanocomposites were characterized by the X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and the vibrating sample magnetometer techniques. The results of characterization suggest that the main magnetic phase present in the nanocomposite is magnetite nanoparticle with an average diameter of 18–23 nm and the saturation magnetization of 74.29 emu g–1. The specific surface area was calculated by a BET single-point method as a rapid and accurate way which can lie almost anywhere on the isotherm. The values of the specific surface area obtained by the BET single-point method were in a good agreement with the BET multiple-point method. It was found that the BET single-point method is faster and simpler than the BET multiple-point method for routine applications. Also, increasing Fe3O4 content caused an increase in the specific surface area of the nanocomposites.