Direct determination of mono, di and triglycerides in biodiesel: a critical analysis of the methodology recommendes and suggestions for some experimental parameters of HT-HRGC, seeking stability and consistency of the measures

Pelisson, Leidimara; Bahia Filho, Oscar; Lanças, Fernando M.

Palavras-chave: Biodiesel, process quality control, high temperature gas chromatography, Brazilian legislation, acylglycerols.

Resumo: Biodiesel is chemically defined as fatty acid mono-alkyl esters derived of vegetable oils, animal fats or discarded greases. The most commonly used process for its production is the based–catalysed transterification in alcoholic alkaline medium in presence of inorganic catalyst. The quality control of the produced biodiesel is essential for its use as fuel. In this sense, the Brazilian National Agency of Petroleum (ANP) suggest different methods with objective to cover all specifications of industrial biodiesel. Gas chromatography is the analytical technique proposed for testing quality control of this product with the quantification of free and bonded glycerol. This paper discusses the various arrangements of GC methods suggested by local legislation and proposes a new methodology for mono, di and triglycerides, as an extension of the resolution ANP 42. The developed methodology presented excellent results for bonded glycerol analyses in samples of oils and biodiesel.

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