Cu/Dy/S_2O_8^(2-)/Al-PILR催化剂制备及其选择催化还原NO

Preparation of Cu/Dy/S_2O_8^(2-)/Al-PILR catalyst and its catalytic performance for selective reduction of NO

采用累托土为原料,合成铝交联累托土(Al-PILR),然后分步浸渍负载(NH4)2S2O8、Dy(NO3)3和Cu(NO3)2,制成Cu/Dy/S2O28-/Al-PILR催化剂。考察该催化剂对C3H6选择性还原NO的催化性能,并且利用低角XRD、BET、Py-IR、IR、TG和SEM等方法,研究催化剂结构与性能的关系。实验结果表明,铝交联剂能很好地撑开累托土的土层,显著增大催化剂的比表面积;S2O28-能明显增加铝交联累托土B(Brnsted)酸的酸量;Dy能进一步增加B酸的酸量,有效提高催化活性和热稳定性。因此,Cu/Dy/S2O28-/Al-PILR催化剂具有良好的催化性能,最佳催化活性温度为300℃,NO转化率高达80.3%,在有10%水蒸气存在的情况下仍可达77.6%。

By using rectorite as raw materials,the Al-pillared rectorite（Al-PILR） was synthetized,then the Cu/Dy/S2O2-8/Al-PILR catalyst was prepared by loading of（NH4）2S2O8,Dy（NO3）3 and Cu（NO3）2 onto the Al-pillared rectorite step by step.The catalytic performance of the Cu/Dy/S2O2-8/Al-PILR catalyst on the selective catalytic reduction of NO with propylene was investigated.The relationship between the structure and the performance of the Cu/Dy/S2O2-8/Al-PILR catalyst was also explored by means of Low-angle X-ray diffraction（LAXRD）,Surface area measurements（BET）,Pyridine absorption infared spectrum（Py-IR）,Infrared spectroscopy（IR）,Thermal gravimetric analysis（TG） and Scanning electron microscope（SEM）.The experimental results indicated that the Al pillaring agent could effectively insert into the layer of rectorite and remarkably enlarge the specific surface area,and S2O82-could obviously increase the Brnsted acid amount of the Al-pillared rectorite,Dy could further increase the Brnsted acid amount to improve the catalytic activity and thermal stability effectively.Therefore,the Cu/Dy/S2O2-8/Al-PILR catalyst exhibited excellent catalytic performance.The NO conversion was up to 80.3% at 300 ℃ and 77.6% even at the presence of 10% volume fraction of water vapor.