钕的添加对V2O5-MoO3/TiO2平板式脱硝催化剂性能的影响

Effect of Neodymium Addition on the Plate-type V2O5-MoO3/TiO2 Catalyst for Selective Catalytic Reduction of NO

摘要:

本文制备了一系列不同Nd含量的V₂O₅-MoO₃-Nd₂O₃/TiO₂平板式脱硝催化剂。采用XRD、N₂-吸附脱附、XPS、H₂-TPR、拉曼光谱和NH₃-TPD等表征手段对催化剂进行分析。结果表明：适量Nd(0.25%、0.5%)的引入,增强了V₂O₅-MoO₃/TiO₂催化剂的还原性能,增加了催化剂的O_α/(O_α+O_β)比率,从而提升了催化剂的脱硝活性。然而,过量Nd(0.75%、1%)的添加,会导致催化剂酸性性能的显著降低,造成催化剂脱硝性能的下降。此外,过量Nd的添加还会对催化剂的耐磨强度有负面影响。各催化剂中,VMoNd(0.5%)/Ti催化剂显示了最佳的脱硝活性。

Abstract:

A series of plate-type V₂O₅-MoO₃-Nd₂O₃/TiO₂ catalysts with different amounts of neodymium were prepared to investigate the impact of neodymium addition on selective catalytic reduction (SCR) of NO with NH₃. XRD, N₂-adsorption, XPS, H₂-TPR, Raman and NH₃-TPD were carried out to characterize the catalysts. It was found that with the suitable addition of Nd (0.25% and 0.5%) to V₂O₅-MoO₃/TiO₂ catalyst not only brought to the improvement of the reduction property, but also increased the O_α/(O_α+O_β) ratio of the catalyst, which leaded to the enhanced catalytic efficiency. However, when the content of Nd was excessive (0.75% and 1%), the acid sites of the catalysts decreased evidently. Accordingly, the catalytic performance of these catalysts was relatively low. What is more, the mechanical property of the catalyst declined when the content of Nd was excessive. Among the catalysts investigated, VMoNd(0.5%)/Ti catalyst had the best catalytic performance.