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以钛酸丁酯、偏钒酸铵和硝酸银为原料,通过溶胶-凝胶法制备了银掺杂低钒负载量的Ag-V/TiO2脱硝催化剂,采用X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、程序升温还原(TPR)、热重-质谱联用(TG-MS)和傅里叶变换红外(FT-IR)光谱进行了表征,并考察了催化剂脱硝性能。结果表明随着银掺杂量的提高,催化剂的低温活性大幅度提升,高温活性先提高后降低,并且催化剂具有良好的寿命。银主要以单质银形式存在,其抑制了催化剂晶粒增大,降低了表面氧的活化能,降低了VO键能,降低了钒的还原温度,从而提高了脱硝性能。

A series of Ag-doped Ag-V/TiO2 catalysts with low vanadium loadings were prepared by the sol-gel methods for selective catalytic reduction(SCR) of NOx with ammonia as reductant,using tetrabutyl titanate,ammonium metavanadate and silver nitrate as raw materials.The catalysts were characterized by X-ray powder diffraction(XRD),X-ray photoelectron spectra(XPS),temperature programmed reduction(TPR),Thermogravimetry-mass spectrometry(TG-MS) and Fourier transform infrared spectroscopy(FT-IR).The activity was also investigated.The results showed that the low temperature activity improved and the high temperature activity increased firstly and then decreased with the increasing of Ag amounts.The durability of the catalysts was good.Silver doping inhibited the growth of crystal size,reduced the activation energy of surface oxygen,the bond energy of VO and the reduction temperature of vanadium oxides.

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