Ni-MFI zeolites with high percentage of Ni (5-15 wt%) were prepared by using an ionic complex [(C4H9)(4)N](2)(+)[Ni(EDTA)](2)(-) by one step synthesis. These molecular sieves were characterized using X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), Fourier-transform infrared spectroscopy (FT-IR), ultraviolet-visible spectroscopy (UV-vis), differential scanning calorimeter (DSC) and nitrogen adsorption-desorption isotherms. The results showed that heteroatom Ni was successfully introduced into the MFI framework up to 15 wt%. Moreover, this Ni-MFI possessed regular and stable structure with high specific surface area and average pore diameter of 388-439 m(2) g(-1) and 2.566-3.828 nm, respectively, compared to MFI prepared by traditional methods. These samples also showed good thermal and hydrothermal stability. (c) 2009 Elsevier Inc. All rights reserved.