Integrated Biodiesel Production by Means of Ultrasonic Energy: A Comparison between Different Homogeneous Catalyst Systems

抄録

The most common catalysts for biodiesel production are homogeneous catalysts such as NaOH and KOH. In the present study, a comparison was performed in the different base and acid catalysts (NaOH, KOH, Na₂CO₃, K₂CO₃, H₂SO₄ and CH₃COOH) for methanolysis and ethanolysis of triolein by means of ultrasonic cavitation. All experiments were carried out under the same experimental condition in a batch ultrasonic reactor at 25°C, where the molar ratio of alcohol to triolein and catalyst concentration were 6:1 and 1 wt%, respectively. The biodiesel conversion was near 100% for all base catalysts. However, it was found that the conversion was very low in the case of acid catalyst (H₂SO₄) and no conversion was observed in the case of CH₃COOH. It was found that the catalytic activity for methanolysis and ethanolysis of triolein was in the order of CH₃COOH (no conversion) ‹ H₂SO₄ ‹ K₂CO₃ ‹ Na₂CO₃ ‹ KOH = NaOH under the ultrasonic irradiation condition.