A series of V₂O₅–WO₃/TiO₂ catalysts treated by KCl or K₂SO₄ were prepared using the equal volume impregnation method. The effects of adding these K salts on SO₂–SO₃ conversion and on denitration behavior over the catalyst were studied, using reactor trials and various characterization methods, including NH₃-TPD, H₂-TPR, ICP, BET, XRD, SEM, FT-IR and XPS. The results of catalytic activity evaluation tests show that adding K salts decreases the denitration efficiency, while SO₂ enhances the activity of the KCl-poisoned catalyst to an extent. The presence of K salts also improves the SO₃ formation rate, such that the SO₃ formation rate for the K₂SO₄-poisoned catalyst is as high as 1.53% at 410 °C (compared with 0.60% for the fresh catalyst). The characterization data indicate that K salts aggregate on the catalyst surface, blocking the pores of the catalyst. The reduction ability of the catalyst is decreased slightly and new weakly acidic sites appear. In addition, the concentration of strongly acidic sites declines. SO₂ can increase the surface acidity of the catalyst. K salts increase the number of V⁵⁺=O bonds and weakly acidic sites, but consume oxygen atoms along with V and W species. Importantly, the strength of the V⁵⁺=O bonds, the concentration of surface chemically adsorbed oxygen and the V⁴⁺/V⁵⁺ ratio all played vital roles in improving the conversion of SO₂–SO₃ and in enhancing the NO reduction.

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采用等体积浸渍法制备了一系列用KCl或K ₂ SO ₄处理的V ₂ O ₅ -WO ₃ / TiO ₂催化剂。使用反应器试验和各种表征方法，包括NH ₃ -TPD，H ₂ -TPR，ICP，BET，XRD，SEM，研究了添加这些K盐对SO ₂ -SO ₃转化率和催化剂上脱硝行为的影响。，FT-IR和XPS。催化活性评估测试的结果表明，添加K盐会降低脱硝效率，而SO ₂在一定程度上增强了KCl中毒催化剂的活性。K盐的存在还提高了SO _3的形成速率，使得K ₂ SO ₄中毒的催化剂的SO ₃形成速率在410℃下高达1.53％（相比之下，新鲜催化剂为0.60％）。表征数据表明，K盐聚集在催化剂表面上，堵塞了催化剂的孔。催化剂的还原能力略有降低，并且出现了新的弱酸性部位。另外，强酸性部位的浓度下降。SO ₂可以增加催化剂的表面酸度。钾盐增加V ⁵⁺的数量= O键和弱酸性部位，但与V和W物种一起消耗氧原子。重要的是，V ⁵⁺ = O键的强度，表面化学吸附氧的浓度以及V ⁴⁺ / V ^5+的比例均对提高SO ₂ -SO ₃的转化率和增强NO的还原起着至关重要的作用。。

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