Catalyst type | number | Clarification time (min) | Yield (%) |
p-toluenesulfonic acid | 1 | 112 | 80.9 |
Concentrated sulfuric acid | 2 | 151 | 78.6 |
p-toluenesulfonicacid+Phosphorous acid | 3 | 105 | 94.8 |
Concentrated sulfuric acid+Phosphorous acid | 4 | 122 | 92.4 |
p-toluenesulfonicacid+concentrated sulfuric acid | 5 | 115 | 89.2 |