Romain Richard

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

Many analytical procedures have been developed to determine the composition of reaction mixtures during transesterification of vegetable oils with alcohols. However, despite their accuracy, these methods are time consuming and cannot be easily used for on-line monitoring. In this work, a fast analytical method was developed to on-line monitor the transesterification reaction of high oleic sunflower oil with ethanol using Near InfraRed spectroscopy and a multivariate approach. The reactions were monitored through sequential scans of the reaction medium with a probe in a one-liter batch reactor without collecting and preparing samples. To calibrate the NIR analytical method, gas chromatography-flame ionization detection was used as a reference method. The method was validated by studying the kinetics of the EtONa-catalyzed transesterification reaction. Activation energy (51.0 kJ/mol) was also determined by considering a pseudo second order kinetics model.

Towards a New Oxidation Process Using Ozone to Regenerate Coked Catalysts

ABSTRACT This work focuses on the regeneration of a zeolite catalyst from industry deactivated by fouling with coke. To replace high temperature combustion, a common and energy intensive process, an oxidation process under milder conditions (50 °C–200 °C) has been investigated using ozone. Coked zeolite has been oxidized by an ozone stream in a fixed bed reactor, and regeneration kinetics was followed by analyzing carbon content of the particles and ozone concentration at the outlet. The effects of temperature, time on stream and ozone inlet concentration on carbon removal efficiency were studied. Moreover, elemental analysis showed that a maximum of 74.3% of carbon could be removed from the coked catalyst after 6.5 h. Moreover, the total specific surface area, the pore size distribution and the total pore volume (mainly mesopores) have been evaluated on coked and regenerated samples.