新型CeO_2-V_2O_5/TiO_2-SiO_2催化剂高效抗碱金属中毒性能

Promotional effect and alkali-resistant performance of novel CeO_2-V_2O_5/TiO_2-SiO_2 catalyst

试验采用SiO2和CeO2对V2O5/TiO2催化剂进行改性并进行催化性能研究,找到了一种最佳比例的Ce10VTiSi0.3催化剂.结果表明,新型的Ce10VTiSi0.3催化剂可以使温度窗口扩大到200~400℃,转化率提高18.54%,具有优秀的抗碱金属中毒性能.改性催化剂可以降低N2O的生成,提高N2的选择性,同时具有较好的抗SO2和抗H2O性能.通过N2-BET、Py-IR等技术手段对催化剂进行表征.结果表明,SiO2和CeO2的加入会使得催化剂的比表面积得到明显的提高,平均粒径下降,孔容积增多.利用吡啶吸附原位红外光谱法进行研究后发现,改性催化剂具有丰富的B酸和L酸,更有利于NH3在催化剂表面的吸附以及表面的氧化还原反应.

The effect of the additive CeO2 and SiO2 on V2O5/TiO2 catalyst for the selective catalytic reduction of NOx with NH3 was investigated.Ce10VTiSi0.3has the best proportion of CeO2 and SiO2and exhibits an excellent SCR performance.The temperature window was broaden to 200-400 ℃.The NO conversion got a 18.54%improvement and the alkali poisoning resistance ability was largely enhanced.A lower production of N2 O was obtained on Ce10VTiSi0.3 which improved N2 selectivity.The modified catalyst displayed an excellent ability over the resistance of SO2 and H2O.The catalysts were characterized by using N2-BET and Py-IR methods.The surface area was largely increased with the addition of CeO2 and SiO2.The Py-IR results show that the revised catalysts get abundant amount of Brnsted acid and Lewis acid,which are positive for the adsorption of NH3 and the redox on the surface.