Nuclear magnetic resonance spectroscopic analysis of ethyl ester yield in the transesterification of vegetable oil : an accurate method for a truly quantitative analysis

Copyright © 2012 John Wiley & Sons, Ltd.

Bibliographische Detailangaben
Veröffentlicht in:Magnetic resonance in chemistry : MRC. - 1985. - 50(2012), 1 vom: 05. Jan., Seite 1-4
1. Verfasser: Mambrini, Giovanni Pimenta (VerfasserIn)
Weitere Verfasser: Ribeiro, Caue, Colnago, Luiz Alberto
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2012
Zugriff auf das übergeordnete Werk:Magnetic resonance in chemistry : MRC
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Esters Plant Oils
Beschreibung
Zusammenfassung:Copyright © 2012 John Wiley & Sons, Ltd.
Biodiesel has recently gained importance as an alternative to fossil diesel. However, the development of more efficient biodiesel formation processes still depends on the use of fast and accurate analytical techniques to evaluate the conversion degree of the transesterification reaction. Nuclear magnetic resonance (NMR) spectroscopy has been used for this purpose, but some experimental details still need to be addressed. Therefore, in this communication, the experimental conditions for a truly quantitative NMR analysis of biodiesel formation are presented. The longitudinal relaxation time (T(1) ), which is the determining factor for quantitative analysis, was measured using an inversion-recovery method, and a maximum value of 2.35 s was obtained for a biodiesel sample. A linear determination coefficient of r(2)  = 0.99 was obtained when a time delay between pulses longer than 5T(1)  =15 s was used, whereas strong deviations were observed when using shorter delays
Beschreibung:Date Completed 23.08.2012
Date Revised 07.03.2012
published: Print-Electronic
Citation Status MEDLINE
ISSN:1097-458X
DOI:10.1002/mrc.2831