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| No. | Transesterification method | Characteristics |
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| 1 | Homogeneous acid-catalyzed transesterification | (i) Relatively insensitive to the FFA content of the raw material relatively more minor energy-intensive |
| (ii) Requires higher operating temperatures and |
| (iii) The resulting biodiesel usually has a higher amount of free glycerol (lower percentage of purity) |
| 2 | Homogeneous base-catalyzed transesterification | (i) Very sensitive to FFA and moisture content |
| (ii) Very selective in the type of raw material |
| (iii) The reaction is fast |
| (iv) The catalyst is relatively inexpensive |
| (v) Usually applied on an industrial scale for biodiesel production |
| 3 | Heterogeneous acid-catalyzed transesterification | (i) Avoids product separation problems and purification |
| (ii) Allows the reuse of the catalyst |
| (iii) Requires relatively high alcohol for oil molar ratio and a long reaction time |
| 4 | Heterogeneous base-catalyzed transesterification | (i) Reduces process steps and minimizes the waste that harms the environment |
| (ii) Easy separation and reuse of catalyst |
| (iii) The catalyst may be poisoned upon exposure to ambient air (not environmentally friendly) |
| 5 | Lipase-catalyzed transesterification | (i) Insensitive to FFA and moisture content |
| (ii) Carried out at low temperature and converting more amount of feedstock into biodiesel |
| (iii) It is expensive because enzymes are expensive and take longer to get good results |
| 6 | Nanocatalyzed transesterification | (i) Not sensitive to FFA |
| (ii) Moisture content was carried out relatively at low temperatures and took a short time |
| (iii) Catalysts can be reused many times at a cost |
| |
| (vi) It requires more alcohol for effective results |
| (vii) In some cases, preparation of the suitable catalyst is expensive |
| 7 | Ionic liquids-catalyzed transesterification | (i) Allows easy separation of the final product because the biphasic formation |
| (ii) Reduces process costs and being efficient and timesaving |
| (iii) Allows modulation of the desired properties of the catalysts when preparing them |
| (iv) The catalyst has high catalytic activity and excellent stability and can be easily separated and reused many times |
| (v) It requires relatively more alcohol for effective results and is usually expensive to own ionic liquid |
| 8 | Supercritical transesterification | (i) Not sensitive to FFA and moisture content of raw materials |
| (ii) Allows to use a broader range of raw materials |
| (iii) Usually takes less time and produces a more significant amount of fuel per mass of feedstock |
| (iv) It requires higher temperature and pressure and consumes more methanol |
| (v) It is not economically profitable because of its high operating costs |
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