Resumo

VALDEZ, Higor da Cal et al. Free and total glycerol determination in biodiesel samples by enzymatic method with colorimetric detection. Quím. Nova [online]. 2012, vol.35, n.3, pp. 601-607. ISSN 0100-4042.  http://dx.doi.org/10.1590/S0100-40422012000300028.

A method based on enzymatic activities was developed using three enzymes (glycerokinase, glycerol-3-phosphate oxidase and peroxidase) and colorimetric detection for the determination of glycerol in biodiesel. The enzymatic conversion of glycerol produces H₂O₂ that is eliminated by the action of peroxidase, an oxygen acceptor and 4- aminoantipirine, producing water and a colored compound, which was analyzed. This method showed good linear correlation coefficient (r = 0.9937) in the concentration range of 4.95 x 10^-5 to 3.96 x 10^-4% (w/w) and had experimental limits of detection and quantitation of 7.10 x 10^-6 and 2.10 x 10^-5% (w/w), respectively.

Palavras-chave : glycerol content; biodiesel; enzymatic-colorimetric method.