Formation of mesoporous alumina at room temperature via combined utilization of acetic acid (as an organic modifier) and cetyl trimethyl ammonium bromide (CTAB) as a cationic surfactant has been investigated in n-heptane medium. The reactants molar ratio was aluminum isopropoxide: acetic acid: water: CTAB: n-heptane, as 1: 1: 3: x: 15, where x was 1 or 3. The calcined materials (at 600 degrees C for 3 h) were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and N-2 adsorption/desorption techniques. Thus, amorphous (weakly crystalline gamma-phase) mesoporous aluminas of possible hexagonal symmetry, high surface area and relatively narrow pore size distribution were obtained. The enhancement of surface area and retardation of crystallization were found to increase with the increasing of CTAB ration in the reaction mixture. (C) 2008 Elsevier B.V. All rights reserved.