This study reports the synthesis of porous nano alumina employing carboxylato-alumoxanes [Al(O) x (OH) y (O2CR) z ] n as precursors for controlling the pore size, pore size distribution and porosity of the alumina, using a new process ecofriendly. The carboxylato-alumoxanes was prepared by the reaction of boehmite with carboxylic acids. The boehmite was obtained by the hydrolysis of aluminum alkoxide in an aqueous solution. The colophony extract is employed as a source of carboxylic acids. The materials were characterized, using XRD, TGA, N2 physical adsorption, SEM, TEM, NMR and FTIR. A mechanism was proposed for the formation of the synthesized structures. TEM measurements confirmed particle size ranged from 5 to 8 nm.

Ceria nanoparticles were synthesized employing chitosan as template and thermal treatment at different temperatures (350, 650, and 960°C). The effect of calcination temperature on structural properties and photocatalytic activity of ceria nanopowder was also tested. Degradation of an azo dye, Congo Red (CR) as a model aqueous pollutant, was investigated by means of photocatalysis of ceria nanoparticles under visible light irradiation. The influence of catalyst amount, initial CR concentrations, and degradation reaction kinetics were studied. The results were compared with commercial CeO₂ at the same degradation conditions.