A series of TiO2 supported manganese oxide catalysts, MnOx/TiO2, were prepared by wet-impregnation method for the low temperature selective catalytic reduction (SCR) of NO with ammonia. WO3 with different loadings was added to MnOyTiO2 samples to investigate its possible influence on the catalytic activity of MnO,/TiO2 by using several characterization techniques including BET surface area, laser Raman spectroscopy (LRS), Fourier transform infrared spectroscopy (FT-IR) , X-ray diffraction(XRD). The research shows that minute addition of 5% WO3 raises the catalytic performance of MnO,/TiO2 catalyst effectively by expanding the carrier' s surface area, improving its thermal resistance, increasing surface Bronsted acids and NH3 adsorption capacity, and broadening the temperature window of SCR reaction. The MnO^-Woj/TiC^ shows better SCR activity than WO3- Mn(X/TiO2 in terms of impregnation sequence. The adsorption peaks of NH3 on surface of catalysts will be weakened or lost with temperature increasing, and the denitration reactivity curve of catalysts shows a maximum with the increase of temperature.%以醋酸锰为前驱物通过浸渍法制备了MnOx/TiO2催化剂,用WO3对载体进行改性制得一系列MnOx-WO3/TiO2催化剂,采用X射线衍射(XRD)、比表面积测定(BET)、拉曼光谱(LRS)、原位红外(FT-IR)光谱等表征技术进行相关的微观表征分析,同时在模拟氨气选择性催化还原NOx( NH3-SCR)的反应条件下对催化剂的脱硝反应活性进行了考察.研究表明,添加5％的WO3拓展了载体的比表面积,提高了催化剂的抗热性,增加了催化剂表面的Br(o)nsted酸位,拓宽其选择性催化还原脱硝活性温度窗口,对MnOx/TiO2催化剂有很好的改性作用；先钨后锰的负载顺序优于先锰后钨；随着温度的升高,化学催化反应速率提高,催化剂表面NH3吸附峰呈减弱或消失趋势,故催化剂脱硝活性温度曲线呈中间高、两头低.
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