| 초록 |
Cu ion exchanged zeolite catalysts is one of the most powerful SCR catalysts because of their high NOx conversion and stability. In this research, we investigated the Cu ion mobility in the chabazite cage. We compare two catalysts, PM-C-SSZ and PM-L-SSZ. The PM-C-SSZ sample was mixed by mortar so it has high to particle interaction. On the other hand, PM-L-SSZ sample was mixed after each particles was sieved separately, so it has loose interaction between particles. In the PM-C-SSZ, Cu ion can move from Cu-SSZ-13 to H-SSZ-13 because each particles contact directly. However, in the PM-L-SSZ sample, Cu ion cannot move to H-SSZ-13 because particles were separated. Migrated Cu ions are located at 2Al sites of H-SSZ-13 which are thermodynamically more stable sites. As Cu ions on 1Al site in the Cu-SSZ-13 move to 2Al sites in the H-SSZ-13, ratio of Cu ions on 2Al site increases. The PM-L-SSZ has higher NH3-SCR activity than the PM-C-SSZ because its high density of Cu ion. |
