| abstract |
The invention relates to a method for analyzing free glycerol (FG) in a biodiesel sample comprising, in particular, fatty acid methyl esters (EMAG) and acylglycerols (MAG, DAG, TAG), characterized in that the methyl esters (EMAG) and the acylglycerols (MAG, DAG, TAG) are separated from the free glycerol (FG) by extraction in solid phase from the sample in at least one silica cartridge (A), eluted, d on the one hand, at least one phase (F1) containing the methyl esters and / or the acylglycerols and, on the other hand, a phase (F2) containing the free glycerol (FG) and then drying the said phase (F2), it is suspended in the ethanol solvent then it is mixed with an enzymatic kit so as to obtain a colored compound (CC) and, said colored compound is analyzed by spectrophotometry in order to measure the concentration of free glycerol (FG) in said sample . Figure 1 |