High purity mesoporous gamma-al(2)o(3) from kano kaolin in the presence of polyethylene glycol 6000 (peg-6000) surfactant

Abstract

Mesoporous gamma-Al2O3 with large surface area and narrow pore size was synthesized from acid-leachates of calcined kaolin in the presence of polyethylene glycol 6000 (PEG-6000) surfactant at room temperature. The synthesized alumina was characterized by X-ray diffraction (XRD), Nitrogen adsorption-desorption, Fourier transform infra-red spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) with energy-dispersive X-ray analysis (EDX), and thermogravimetric-Derivative thermal analysis (TG-DTA). High-purity mesoporous gamma-Al2O3 with large surface area of 365.1 m(2)/g, narrow pore size distribution centred at 5.3 nm and pore volume of 0.46 cm(3)/g was obtained at 500 degrees C. When the calcination temperature has increased to 700 degrees C, the surface area decreased to 272.9 m(2)/g. Crystallite size calculated using Scherer's equation revealed the average size of 4.33 and 4.12 nm for alumina calcined at 500 and 700 degrees C, respectively. The excellent pore structural properties (high surface area and large pore volume) of the synthesized mesoporous gamma-alumina in the present study will allow for higher loading of active catalytic phases, as such it can be used as catalyst support.