Synthesis of Mesoporous g-Al2O3 Templated with Rosin-Based Quaternary Ammonium Salt by Ammonia Precipitation

Abstract

Mesoporous alumina were successfully synthesized by a facile method of ammonia precipitation with rosin-based quaternary ammonium salt. Their structures were characterized with X-ray diffraction, N₂ adsorption and desorption, transmission electron microscopy and thermal gravimetry-differential scanning calorimetry. The boehmite phase was achieved for precursors by ammonia precipitation, so that g-Al₂O₃ was easily prepared after the calcination at 550 ºC for 4 h. These calcined materials possessed wormhole-like mesopores without long range packing order but with a fairly uniform pore size. The rosin-based quaternary ammonium salt dosage and aging temperature had great impact on the properties of the alumina. When the dosage of rosin-based quaternary ammonium salt was 1.6 g and the aging temperature was 90 ºC, the maximum BET surface area (271 m² g^-1), pore volume (0.59 cm³ g^-1) and pore size (6.39 nm) were obtained.