Thermochemolysis – A Simple and Rapid Methylation Method Based on TMAH for Gas Chromatographic Analysis of Linseed Oil and Amber

In order to improve pyrolysis chromatographic analysis of materials that release polar functional groups e.g. carboxylic acids, a simple and rapid methylation method based on TDUpyrolysis/GC-MS in the presence of tetramethylammonium hydroxide (TMAH) was developed. Linseed oil was selected as test material because of its high triglyceride content comprising both saturated and unsaturated fatty acids. Pyrolysis was performed at 500, 600 and 700°C using a GERSTEL pyrolysis module (PYRO) with a heated platinum fi lament. The optimum pyrolysis temperature for linseed oil was found to be 500°C. The fatty acids in the linseed oil were found to have been quantitatively methylated when using a methanolic TMAH solution (~ 10 % in methanol). The use of an aqueous TMAH solution (25 wt. % in H2O) for the methylation of fatty acids was found to result in lower fatty acid methyl ester (FAME) yields, indicating that