A porous composite of ceria and lanthana/g-alumina was prepared by inverse microemulsion method. The precursor is heatedat several calcination temperature between 823 to 1123 K. Also, the effect of different molar ratio of Ce : La on thecrystallization was studied. The study of X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electronmicroscopy (SEM) and temperature programmed reduction (TPR) suggested that well crystalline nanosized particles areobtained. The product samples possess mesoporosity with broadly distributed pores between 14 to 22 nm diameter. Surfacearea increases by increasing the calcination temperature. Also, the particle size of the composite samples decreases with anincreasing in molar ratio of Ce : La.

Keywords: Reverse micelle, Cerium oxide, Lanthanum oxide, Aluminum oxide, Triton X- 114, Calcination temperature