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A series of meso-microporous Cu-SAPO-34 catalysts were successfully synthesized by a one-pot hydrothermal crystallization method, and these catalysts exhibited excellent NH_3-SCR performance at low temperature. Their structure and physic chemical properties were characterized by means of X-ray diffraction patterns(XRD), Scanning electron microscopy(SEM), Transmission electron microscopy(TEM), N_2 sorption-desorption, nuclear magnetic resonance(NMR), Inductively Coupled Plasma-Atomic Emission spectrometer(ICP-AES), X-ray absorption spectroscopy(XPS),Temperature-programmed desorption of ammonia(NH_3-TPD), Ultraviolet visible diffuse reflectance spectroscopy(UV-Vis DRS) and Temperature programmed reduction(TPR).The analysis results indicate that the high activities of Cu-SAPO-34 catalysts could be attributed to the enhancement of redox property, the formation of mesopores and the more acid sites. Furthermore, the kinetic results verify that the formation of mesopores remarkably reduces diffusion resistance and then improves the accessibility of reactants to catalytically active sites. The 1.0-Cu-SAPO-34 catalyst exhibited the high NO conversion(> 90%) among the wide activity temperature window in the range of 150–425℃.
A series of meso-microporous Cu-SAPO-34 catalysts were synthesized by a one-pot hydrothermal crystallization method, and these catalysts exhibited excellent NH 3-SCR performance at low temperature. Their structure and physic chemical properties were characterized by means of X- ray diffraction patterns (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), N2 sorption-desorption, nuclear magnetic resonance (NMR), Inductively Coupled Plasma-Atomic Emission Spectrometer Spectroscopy (XPS), Temperature-programmed desorption of ammonia (NH3-TPD), Ultraviolet visible diffuse reflectance spectroscopy (UV-Vis DRS) and Temperature programmed reduction (TPR). The analysis results indicate that the high activity of Cu-SAPO-34 catalysts could be attributed to the enhancement of redox property, the formation of mesopores and the more acid sites. Furthermore, the kinetic results verify that the formation of mesopores remarkably reduces di The 1.0-Cu-SAPO-34 catalyst showed the high NO conversion (> 90%) among the wide activity temperature window in the range of 150-425 ° C.