Method EN 14331 specifies the LC separation and characterization of FAMEs in blended biodiesel. To monitor compliance with EN 14331, a sensitive and reliable analytical method is needed to detect the contents of biodiesel. The analysis is usually performed by gas chromatography (GC) with a Flame Ionization Detector (FID), due to the highest resolution compared to LC separation. However, the analysis of high boiling triglycerides by GC requires an accurate choice of the injector, as well as of the column and overall operating conditions, in order to avoid any sample discrimination and/or degradation.
In general, LC/MS methods can be adapted for nonvolatile component analysis but have not been generalized in the regulatory analysis because traditional LC/MS instrumentation suffered contamination to the LC/MS interface as a result of the complicated and dirty sample matrices. Without rigorous sample preparation, the MS would become contaminated and clogged by sticky residue build-up on the LC/MS interfaces.
Some of these problems can be avoided by having the biodiesel samples separated and detected by the Thermo Scientific Accela™ high speed LC and the MSQ Plus™ using electrospray ionization (ESI) . A cone wash is used to prevent interface contamination and clogging.
Complete the form on this page to download a technical poster describing an LC/MS method for Biodiesel analysis. |