| 초록 |
As the regulations of emission are getting stricker, the decrease of CO, NOx, and hydrocarbon emission is needed. The three-way catalysts (TWCs), which oxidize emitted hydrocarbons, are activated over ~200-300 °C, and TWC-inactivated period is called as a cold start period. In the cold start period, ~80% of total hydrocarbons emission are directly released. One of the strategies to reduce the hydrocarbon emission is a hydrocarbon trap. A ZSM-5, a representative MFI type zeolite, is highly attracted as a hydrocarbon trap due to its appropriate pore size and its affinity to hydrocarbons. Here, we prepared two types of ZSM-5 particles with different cations, Na-form and H-form ZSM-5 (NaZ and HZ). We employed ~5 wt% of Cu within ZSM-5s making CuNaZ and CuHZ. With the various characterizations, we demonstrate the states of copper within CuNaZ and CuHZ. We also carried out the cold start tests of different ZSM-5s and figured out that CuHZ shows the best efficiency on removal of hydrocarbon. |
