Affiliation:
1. School of Metallurgy and Materials Engineering, Iran University of Science & Technology (IUST), Narmak, Tehran, Iran
2. Space Transportation Research Institute, Tehran, Iran
Abstract
Sol-gel/oil-drop granulation technique was used to prepare mesoporous ?-Al2O3
granules of 1.5-2mm with high specific surface area and pore volume of
295m2/g and 0.47 cm3/g, respectively. The structure of granules was studied
using powder XRD, DTA, TEM and N2 adsorption/desorption techniques. A
response surface methodology (RSM) holding CCD approach was used for
modelling the influence of process variables on the granule pore structure,
having a quadratic function relating the independent variables (calcination
temperature, acid amount and ammonia concentration) to the responses
(specific surface area, mean pore diameter and pore volume). The interaction
effect of variables on each response was studied and all were in acceptable
accordance with experimental values. Accordingly, the granules synthesized
using 20ml of nitric acid, aged in a 9.25wt.% ammonia solution and calcined
at 450?C showed the best properties. The predicted values for the specific
surface area and pore volume were 315.64m2/g, 7 nm and 0.53 cm3/g,
respectively, which were compatible with experimental values.
Publisher
National Library of Serbia