CATL 24 |
| Jifei Jia, Center for Catalysis and Surface Science, Northwestern University, 2137 Sheridan Road, Evanston, IL 60208 and Katsuomi Takehira, Department of Applied Chemistry, Hiroshima University, Kagamiyama 1-4-1, Higashi-Hiroshima, Japan. |
| The pyrolysis of CH4 to H2 and carbon fibers over MCM-41 supported Ni catalyst has been investigated at different temperatures. The initial conversion of CH4 at 873 K is higher than it is at 773 K, but the deactivation at 873 K occurs rapidly. The investigations with SEM and TEM techniques indicate that the pyrolysis of CH4 generates mainly solid carbon fibers at 773 K but mostly hollow ones at 873 K on Ni/MCM-41. Ni metal particles have hardly been found on the tip of or inside the carbon fibers. Raman spectroscopic studies suggest that the carbon fibers formed at 873 K are more graphitic than those obtained at 773 K. The temperature-programmed reactions with O2 (TPO) and H2 (TPH) reveal that the solid carbon fibers formed at 773 K show higher reactivity towards O2 and H2 than the hollow ones formed at 873 K. |
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Plasma Technology and Catalysis
1:30 PM-4:45 PM, Tuesday, March 25, 2003 Convention Center -- Room 342, Oral
Catalysis & Surface Science Secretariat |