A series of CrOx–CeO2/Ti-PILC(PILC is pillared interlayered clay)catalysts for n-butylamine oxidation were prepared using an impregnation method,and the structures,surface acidity distributions,and redox properties of the catalysts were characterized using X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,H2temperature-programmed reduction,and NH3temperature-programmed desorption.The results show that addition of an appropriate amount of CeO2enhances the interactions between Cr and Ce,and this increases the acid strength and mobility of active oxygen species on the catalyst.8CrCe(6:1)/Ti-PILC(12,20)exhibits the best catalytic performance and control of NOxin n-butylamine oxidation.
HZSM-5, Al_2O_3, TiO_2 and SiO_2 supported CeO_2-ZrO_2-CrO_x catalysts were prepared by deposition-precipitation method and tested for deep catalytic oxidation of 1,2-dichloroethane(DCE), as one of the common chlorinated organic pollutants. All the catalysts were characterized by means of N_2 adsorption-desorption, X-ray photoelectron spectroscopy(XPS), ammonia-temperatureprogrammed desorption(NH_3-TPD) and hydrogen temperature-programmed reduction(H2-TPR). The characterization results revealed that there was strongly synergistic effect between the oxidizability of CZCr species and the acidity of supports, which obviously promoted the catalytic activity for DCE degradation. 20% CZCr/HZSM-5 showed the highest activity and good durability during the long-term continuous test. The catalytic activity decreased in the order: 20%CZCr/HZSM-5〉CZCr〉20%CZCr/TiO_2〉20%CZCr/Al_2O_3〉20%CZCr/SiO_2.