Preparation of highly porous γ-alumina via combustion of biorenewable oil

Abstract

Highly mesoporous, transparent γ-alumina particulates were successfully prepared through a new method that circumvents drying processes in sol–gel-based synthetic methods. Upon using a biorenewable oil, the new method affords high porosity (80–88%), high surface area (295–375 m2 g−1) γ-alumina products with controlled pore sizes (average pore diameter = 11–21 nm), by achieving rapid solvent removal and calcination simultaneously through a single combustion step. The products were characterized by elemental analysis, powder X-ray diffraction, solid-state NMR, and high-resolution transmission electron microscopy with selected area electron diffraction for morphology and structure identification, ATR-IR spectroscopy for surface chemistry and functional groups, and nitrogen adsorption/desorption analysis for pore properties. The promising results indicate that the new method may be suitable for high-volume production of highly porous metal oxides with aerogel-like pore architectures.