Table 2 Orthogonal experimental design of optimization study for oleic acid esterification
| Â | Experimental variables | Â | Â | Â | Â |
|---|---|---|---|---|---|
No. | Catalyst loading (percentage based on weight of oleic acid) | Molar ratio oleic acid:methanol | Temperature (°C) | Reaction time (h) | Oleic acid conversion rate (%) |
E1 | 1 | 1:6 | 60 | 5 | 71.9 |
E2 | 1 | 1:9 | 70 | 5 | 81.3 |
E3 | 1 | 1:12 | 80 | 5 | 85.6 |
E4 | 3 | 1:6 | 70 | 5 | 91.5 |
E5 | 3 | 1:9 | 90 | 5 | 92.7 |
E6 | 3 | 1:12 | 60 | 5 | 93.6 |
E7 | 5 | 1:6 | 80 | 5 | 93.4 |
E8 | 5 | 1:9 | 60 | 5 | 92.6 |
E9 | 5 | 1:12 | 70 | 5 | 95.8 |