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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N2;在36000 h-1的空速下,在300~620℃之间,还能将60%的NO x转化成N2。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。
The Cu-SAPO-34 molecular sieve was directly synthesized into honeycomb cordierite by hydrothermal synthesis technology to study the ability of selective catalytic reduction of NO x in the tail gas of diesel engine. The morphology, structure, Cu content and valence state of the monolith catalyst were characterized by SEM, XRD, ICP and XPS. The results show that the active Cu in the Cu-SAPO-34 / cordierite monolithic catalyst prepared by in-situ preparation has a high activity of selective catalytic reduction of NO x. The optimum loading of Cu is 0.30% ~ 0.40 %. Most of the NO x can be catalytically reduced to N 2 at a space velocity of 12,000 h -1 at a temperature between 400 and 670 ° C; at a space velocity of 36,000 h -1 between 300 and 620 ° C 60% of NOx can be converted into N2. After hydrothermal aging, the catalyst retains its catalytic activity better, indicating that the catalyst has better hydrothermal stability.