Abstract
The direct gas-phase oxidation of propylene with molecular oxygen was carried out over Ti-MCM-41 impregnated with metal nitrates to produce propylene oxide (PO) selectively. The effects of Ti-loading on MCM-41, nitrate additives, acid treatment of the support, and the presence of molecular oxygen were investigated. The PO yield increased with increasing Ti content of Ti-MCM-41 and reached a maximum at an optimum Si/Ti ratio of 100. Calcium nitrate was the most suitable additive among various nitrates of alkali and alkaline earth metals investigated, and the acid treatment of Ti-MCM-41 effectively improved its catalytic performance for the PO formation. The presence of both nitrate and molecular oxygen was essential for the PO formation. A synergetic mechanism between the Ti species and metal nitrate was proposed to be responsible for the selective formation of PO.
| Original language | English |
|---|---|
| Pages (from-to) | 169-176 |
| Number of pages | 8 |
| Journal | Catalysis Today |
| Volume | 71 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - 15 Nov 2001 |
| Externally published | Yes |
| Event | Challenges in Alkane Activation and Selective Oxidation (UEDA S.I.) - Yokohama, Japan Duration: 30 Nov 2001 → 30 Nov 2001 |
Keywords
- Direct gas-phase oxidation
- Metal nitrates
- Ti-MCM-41