Cu-SAPO-34/堇青石的原位制备及其催化脱除柴油机车尾气中NO x

利用水热合成技术将Cu-SAPO-34分子筛直接合成到蜂窝状堇青石上，研究模拟柴油机车尾气中选择性催化还原NO x的能力。采用SEM、XRD、ICP和XPS表征整体式催化剂的形貌、结构、Cu含量和价态变化。结果表明：原位制备技术制备的Cu-SAPO-34/堇青石整体催化剂中的活性金属Cu具有很高的选择性催化还原NO x的活性，Cu的最佳上载量质量分数为0.30%-0.40%。在12000 h-1的体积空速下，在400-670℃之间，可将大部分的NO x催化还原成N 2；在36000 h-1的空速下，在300-620℃之间，还能将60%的NO x转化成N 2。水热老化后的催化剂较好的保持催化活性，表明催化剂具有较好的水热稳定性。

One-step hydrothermal synthesis of Cu-SAPO-34/cordierite and its catalytic performance on NOx removal from diesel vehicles

Cu-SAPO-34/cordierite catalysts were prepared via one-step hydrothermal synthesis method and their performances to remove NO x from the diesel vehicle exhaust were evaluated. The morphology, structure, Cu content and valence state were characterized by SEM, XRD, ICP and XPS, respectively. The experimental results show the active component Cu of the catalysts via in situ synthesis could significantly improve the selective catalytic reduction （SCR） activities of NOx and the optimal Cu content is in the range of 0.30%-0.40%（mass fraction）. No N 2 O is detected by gas chromatograph （GC） during the evaluation process, which implies that NOx is almost entirely converted to N2 over Cu-SAPO-34/cordierite catalyst. The conversion rate of NOx to N2 by NH3 over catalyst could almost be up to 100%in the temperature range of 300-670 ℃with a space velocity of 12000 h-1 and it is still more than 60% at 300-620 ℃ under 36000 h-1. The catalysts also show the good hydrothermal and chemical stability at the atmosphere with H 2 O.