Preparation and performance of ceria doped two-component deNO_x monolithic catalysts at low temperature

The (V-W-Ti-O)_x(Cu-Al-O)_1-x(Ce-O)_0.03, (x=0.9, 0.8) deNO_x monolithic catalysts were prepared by low temperature co-sintering (LTC) within the sintering temperature range of 650-850°C. The effects of sintering temperature on the mechanical strength, porosity and water absorption of the monolithic catalysts and the effect of reaction temperature on catalytic activity were investigated. The microscopic structure of the catalysts was analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and fourier infrared spectroscopic analysis (FT-IR). Results show that catalysts are porous in micro-structure and grains are distributed uniformly. The crystallographic forms are mainly TiO₂(rutile), TiVO₄, WV₂O₆, CeVO₄, Cu₂V₂O₇, AlV₂O₄, CuAlMnO₄ and Cu_1.9V₁₂O₂₉. For the reforming monolithic catalysts sintered at 700°C for 2 h, the two-component catalysts exhibit high catalytic activities in the low temperature range of 100-200°C and their bending strength reaches to 45.5 MPa. The NO conversion of (V-W-Ti-O)_0.8(Cu-Al-O)_0.2(Ce-O)_0.03 monolithic catalyst corresponds to 75.9% at reactor temperature of 150°C.