Fe2O3/Al2O3 powders with a range of Fe/Al compositions were prepared by a gel evaporation method to investigate the effect of alumina on the product phases, magnetic properties and simultaneous adsorption of Ni2+ (a model heavy metal cation), NH4+ (a model eutrophication-related cation) and H2PO4- (a model harmful anion). Precursor gels were prepared by dissolving Fe(NO3)(3)center dot 9H(2)O and AI(NO3)(3)center dot 9H(2)O in ethylene glycol, evaporating to dryness, grinding and heating at 300-1000 degrees C for 5 h. The crystalline products were gamma-Fe2O3 (maghemite), formed at 300-600 degrees C, or alpha-Fe2O3 (hematite) and AlFeO3, formed >600 degrees C. The temperatures of the phase change from gamma-Fe2O3 to alpha-Fe2O3 increased with increasing alumina additions. The resulting lattice parameters suggest that Al3+ is incorporated into these phases up to about 15 mol.% at 300 degrees C, falling to 11 mol.% in the gamma-Fe2O3 formed at 600 degrees C. The alpha-Fe2O3 formed at 700 degrees C contained 6 mol.% Al, increasing to 14 mol.% at 1000 degrees C. The magnetic properties of the samples were measured using a vibrating sample magnetometer. The saturation magnetization values of the gamma-Fe2O3-containing samples increased with the addition of alumina to a maximum value of 61 emu/g in the sample containing 95 mol.% Fe2O3 heated at 400 degrees C. The simultaneous adsorption of Ni2+. NH4+ and H2PO4- from water was investigated by a batch method. The highest adsorption values were found for the sample containing 80 mol.% Fe2O3 heated at 600 degrees C, which contained both gamma-Fe2O3 and alpha-Fe2O3. It was therefore concluded that the addition of alumina to iron oxide affects the crystalline phases and phase changes, and enhances the simultaneous cation and anion uptake ability of the materials. (C) 2009 Elsevier B.V. All rights reserved.