| 초록 |
The present study has been focused on an on-stream stability of silica-supported Pt nanocrystallites for the selective reduction of N2O by H2 at low temperatures, such as 90oC-135oC. Samples of the supported Pt with its different loadings were prepared using an ion exchange technique and characterized by H2 adsorption, XRD, HRTEM and in situ DRIFTS measurements. Both activity and stability in this N2O reduction with the catalysts were strongly dependent on the amounts of Pt and its nanoparticle sized, the ratio of H2/N2O fed, and the reaction temperatures chosen, In case that a sample of 1.72% Pt/SiO2 was employed for the reduction at 90oC, it was very difficult to obtain a steady-state N2O conversion, which might be associated with the pore blockage by H2O that is produced during the reaction. At higher temperatures, such as 135oC, the extent of such deactivation was significantly improved.The supported catalysts consistingof small Pt nanoparticles less than5 nm possessed abetter stability for the N2O reduction in the presence of H2. |
