[Application of gas chromatography in research of biodiesel processing]

Applications of gas chromatography in the research of biodiesel processing are reviewed with 27 references, including the analysis of fatty acid methyl esters (FAME) in the reaction products and final biodiesel, the determination of mono-, di- and tri-glycerides, the contents and distribution of free fatty acids, and the determination of trace methanol in biodiesel. The effects of various factors for analysis of the reaction products are discussed, such as injection mode, column type and silylation. A method for the determination of trace methanol in biodiesel products with dual-columns and pressure backflush system is proposed. 1-Propanol was used as the internal standard. After methanol and 1-propanol entered the analytical column through pre-column, the pressure was changed to backflush the heavy components through the split vent. A polar PEG-20M column was applied for the analysis of the contents and distribution of FAME in biodiesels from 8 different vegetable oils.