Rapid determination of flash point and cold filter plugging point for biodiesel blending with diesel by use of FTNIR

In order to establish correlations with closed cup flash point (FP) and cold filter plugging point (CFPP) for biodiesel blending with diesel, FTNIR spectra of biodiesel blending with diesel and basic data obtained form standard methods are treated by partial least squares (PLS) and the relationship between these two indicators and mixing ratio are described initially in this paper. The method can be used for low-cost and rapid determination of indicators mentioned above. The result showed that the linear correlation between these two models predictions and true values measured by standard methods all are significant on the recommended rank (Rec) by OPUS spectroscopy software after models are optimized. It has convenient, low error, low cost and etc advantages when these two models are used to determine closed cup FP and CFPP of for unknown biodiesel blending with diesel, and Mahalanobis distance (MahDist) can be used to limit exception item, else are in the permissible range except few samples. For a new type of biodiesel, the model can be extended by adding 10 more new blend samples. The model so obtained will provide more accurate results for FP and CFPP of this type of biodiesel. The method could be a new method about determination of FP and CFPP for biodiesel blending with diesel, which is easy to spread. It will have a certain practical significance if Near Infrared physical and chemical indicators analyzer for biodiesel is able to be developed by use of this method.