Effects of Na+ on Cu/SAPO-34 for ammonia selective catalytic reduction
Effects of Na+ on Cu/SAPO-34 for ammonia selective catalytic reduction
复制标题
Na对Cu/SAPO-34氨选择性催化还原的影响
DOI：
10.1016/j.jes.2017.11.002
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发表时间：
2018
影响因子：
6.9
通讯作者：
Li Wei
中科院分区：
文献类型：
--
作者：
Wang Can;Wang Chen;Wang Jun;Wang Jianqiang;Shen Meiqing;Li Wei
铜交换菱沸石（Cu/CHA）催化剂已被发现受到碱金属和碱土金属离子的影响。然而，Na+离子对Cu/SAPO-34氨选择性催化还原（NH3-SCR）性能的影响尚不清楚。为了研究其机理，合成了五种不同钠含量的样品并进行了表征。观察到引入的Na+与Cu/SAPO-34的H+和Cu 2+进行离子交换。H+的交换比孤立的Cu ~（2+）的交换容易。交换后的Cu ~（2+）离子发生聚集，形成“类CuAl_2 O_4”物种。Cu/SAPO-34催化剂的NH3-SCR活性随着Na含量的增加而降低，Cu 2+和酸性中心的丧失是导致催化剂活性降低的主要原因。
Copper-exchanged chabazite (Cu/CHA) catalysts have been found to be affected by alkali metal and alkaline earth ions. However, the effects of Na+ions on Cu/SAPO-34 for ammonia selective catalytic reduction (NH3-SCR) are still unclear. In order to investigate the mechanism, five samples with various Na contents were synthesized and characterized. It was observed that the introduced Na+ion-exchanges with H+and Cu2 +of Cu/SAPO-34. The exchange of H+is easier than that of isolated Cu2 +. The exchanged Cu2 +ions aggregate and form “CuAl2O4-like” species. The NH3-SCR activity of Cu/SAPO-34 decreases with increasing Na content, and the loss of isolated Cu2 +and acid sites is responsible for the activity loss.