This Application Note describes the analysis of free and total glycerol in B-100 biodiesel methyl esters using the Agilent Select Biodiesel for Glycerides metal capillary (UltiMetal) GC column in high temperature conditions.
This document details a method for determining free and total glycerol contents in fatty acid methyl esters (FAMEs) using the Agilent Select Biodiesel for Glycerides metal capillary (UltiMetal) GC column. The method is suitable for FAME from rapeseed, sunflower, and soybean oils and is designed to handle high-temperature conditions without column breakage.
The procedure involves derivatizing the sample with pyridine and N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA) to transform glycerol and glycerides into volatile derivatives. These are then analyzed via gas chromatography with a flame ionization detector (FID). The document provides experimental conditions, sample preparation steps, and presents results from various biodiesel samples, including calibration curves and regression coefficients.
| Detection range for free glycerol | 0.005 to 0.05 mass % |
|---|---|
| Detection range for total glycerol | 0.05 to 0.5 mass % |
| Column dimensions | 0.32 mm x 10 m, 0.1 pm |
| Carrier gas | Helium |
| Detector temperature | 380 °C |
It is not suitable due to the problem of peak overlap.
Requirements are < 0.02 mass % for glycerol and < 0.240 mass % total glycerol.