Sol-gel synthesis and characterization of novel La, Mn and Fe doped zirconia: Catalytic combustion activity of trichloroethylene

摘要

Pure zirconia and novel 0.5 wt% La, Mn and Fe doped zirconia powders were synthesized by the sol-gel method. The samples obtained were characterized by thermal analysis (DTA/TGA), infrared spectroscopy (FT-IR), and X-ray diffraction (XRD). The textural properties of the catalysts were studied through N-2 sorption isotherms measured at 77 K. In order to study the influence of the doping metals on the ZrO2 crystalline phase formation, different doping metal loadings were employed. It was found that the ZrO2 monoclinic phase is favored at 800 degrees C when using a La-Mn doping combination, while the tetragonal structure was promoted by a La-Fe doping mixture. The morphology of the get particles was seen to be influenced by the nature of the doping metal; scanning electron microscopy served to observe this phenomenon. Textural analysis by N-2 sorption revealed that were obtained porous materials. The La-Fe zirconia catalyst resisted the high concentration trichloroethylene flow and kept its activity as the temperature was increased. The catalytic activity tests showed that the ZrO2 tetragonal phase stabilized by La, Fe doping agents significantly improved the catalytic combustion of trichloroethylene. (C) 2007 Elsevier B.V. All rights reserved.