Synthesis and physicochemical characterizations of nanostructured Pt/Al2O3-CeO2 catalysts for total oxidation of VOCs

Pt/Al2O3-CeO2 nanocatalysts with Pt loading of 1% and ceria loading of 10,20 and 30% were successfully prepared via wet impregnation method to be utilized in catalytic oxidation of BTX. The nanocatalysts were characterized using XRD, FESEM, TEM, N-2 adsorption, FIN and TPR-H-2 techniques. The XRD patterns confirmed the formation of cerium oxide as the crystalline phase on alumina with the average crystallite size of 8.1-8.7 nm, derived by Scherrer equation. FESEM images confirmed that these nanocatalysts had ceria particles in nano-ranges. TEM analysis showed that platinum particles were fairly well dispersed on Al2O3-CeO2 with an average size of 5-20 nm. BET surface area presented large surface area for nanocatalysts. TPR patterns showed that by adding 1% platinum to support, the reducibility is highly increased. These patterns also revealed the promoting effect of ceria on reducibility of Pt and Al2O3. The results of toluene oxidation indicated that the synthesized nanocatalysts were highly active and able to remove nearly 100% of toluene and xylene and about 85% of benzene as representative VOCs. The presence of nanoparticles along with good characteristics of the synthesized nanocatalysts presented them as highly efficient materials for catalytic oxidation of VOCs. (C) 2010 Elsevier B.V. All rights reserved.