Medium-resolution flow-through NMR spectroscopy for on-line monitoring of biodiesel production under the fume hood.

MARIO H. M. KILLNER; YAMILA GARRO LINCK; ERNESTO DANIELI; J. ROHWEDDER; BERNHARD BLÜMICH

Guildford

Conferencia; MRPM11 - Magnetic Resonance in Porous Media; 2012

Biodiesel is an alternative fuel composed of mono-alkyl esters. It is obtained mainly from the base-catalyzed transesterification reaction of oils or fats. To obtain a highquality fuel and to achieve the requirements for commercialization it is important to monitor the transesterification process to ensure low levels of mono- and diacylglycerols in the biodiesel fuel, resulting from incomplete reactions. For this purpose a desktop, medium-resolution, 1T NMR system, built from permanent magnets, was used to monitor the progress of the reaction on-line. The transesterification reaction of vegetable oil was carried out under the chemistry hood where also the magnet was placed. The reaction mixture was pumped through the magnet bore where it was measured and then returned to the reaction flask. Different feed stocks and catalyst concentrations were analyzed. To determine the biodiesel conversion rate during the reaction progress a Partial Least Squares calibration model was developed and applied to the NMR spectra. The model was validated and the value of the Root Mean Square Error of Prediction (RMSEP) found for the reaction conducted at 27° C was 1.02% (of conversion).