Synthesis, characterization, ion exchange, and catalytic properties of nanobinary and ternary metal oxy/hydroxides

Abstract

Nanobinary (Mg-Al) and ternary (Ni-Mg-Al) metal oxy/hydroxides were synthesized by aerogel protocol. The key features of this method are homogenization of metal organic precursors in methanol-toluene mixture, controlled hydrolysis, gelation, hydrothermal treatment, and finally supercritical drying of solvent. The obtained materials, which on further drying at 120 °C, display high surface area, >500 m² g^-1, and smaller particle size, <20 nm. The samples were further characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric and differential thermal analysis (TG-DTA), and solid state ²⁷Al nuclear magnetic resonance (NMR). The ion exchange and catalytic properties of the resulting nanomaterials were compared with hydrotalcite-like layered double hydroxides (LDHs) prepared by a conventional coprecipitation method. The nanoternary system exhibits 2-4-fold increase in activity of pre-reforming of naphtha.