The commercial value of cashew nut shell liquid (CNSL) has become a cornerstone of the agrowaste industry. It is the by-product of the cashew industry and has an 1/8 inch thickness of soft honeycomb structure. CNSL contains phenolic lipids with aliphatic chains such as anacardic acid, cardanol, cardol and methyl cardol, and their derivatives. The developed GC-MS method is rapid, accurate and selective using a selected derivatizing reagent, namely N-methyl-N-(trimethylsilyl)-trifluoroacetamide that was previously diluted 1:1% with anhydrous pyridine. The proposed GC-MS method was applied for the analysis of different CNSL samples. The results showed that all classes of CNSL compounds were detected. The four alkyl phenols were detected with their different alkyl sidechains without any interference. This method is also specified for the detection of fatty acids of saturated and unsaturated chains. Silylation did not cause any alteration in the chemical structure of CNSL compounds regardless of esterification action. Silylation is considered a safe derivatizing agent compatible with GC chromatography and specific for all volatile and nonvolatile polar and nonpolar CNSL compounds that could be detected in CNSL samples.
Keywords: GC-MS; anacardic acid; cashew nut shell liquid; phenolic compounds.
© 2019 John Wiley & Sons, Ltd.