On-line monitoring of the transesterification reaction between triglycerides and ethanol using near infrared spectroscopy combined with gas chromatography

► The biodiesel produced from sunflower oil and ethanol is of 100% renewable origin. ► EtONa is used as a homogeneous catalyst. ► We on-line monitor the transesterification reaction using Near InfraRed spectroscopy. ► A multivariate approach is used to establish calibration models. ► Activation energy of the reaction was determined (51.0 kJ/mol).