Direct reaction between silicon and methanol over CuCl catalyst with different CuCl loadingsa.
| CuCl/Si weight ratios | Reaction temperatures (°C) | Methanol conversions (%) | Trimethoxysilane | Tetramethoxysilane | ||
|---|---|---|---|---|---|---|
| Selectivities (%) | Yields (%) | Selectivities (%) | Yields (%) | |||
| 3 : 100 | 220 | 0.1 | 87.1 | 0.1 | 12.9 | 0.01 |
| 240 | 60.5 | 79.8 | 48.3 | 20.2 | 12.2 | |
| 260 | 81.4 | 62.3 | 50.7 | 37.7 | 30.7 | |
| 5 : 100 | 220 | 0.5 | 93.2 | 0.5 | 6.8 | 0.03 |
| 240 | 90.4 | 89.6 | 81.0 | 10.4 | 9.4 | |
| 260 | 95.2 | 84.0 | 80.0 | 16.0 | 15.2 | |
| 8 : 100 | 220 | 0.5 | 94.2 | 0.5 | 5.8 | 0.03 |
| 240 | 89.3 | 91.6 | 81.8 | 8.4 | 7.5 | |
| 260 | 97.2 | 81.5 | 79.2 | 18.5 | 18.0 | |
| 10 : 100 | 220 | 0.1 | 91.7 | 0.1 | 8.3 | 0.01 |
| 240 | 90.2 | 87.7 | 79.1 | 12.3 | 11.1 | |
| 260 | 98.4 | 84.0 | 82.7 | 16.0 | 15.7 | |
a
The CuCl/Si mixtures were pretreated at 200 °C for 2 h in a N2 stream with a flow rate of 20 mL min−1. The CuCl/Si mixture was 40 g and the methanol flow rate was 6 mL h−1.