Biodiesel fuel property specifications

TABLE 2.2 Fuel Property Specifications in Biodiesel Standards... 

However, one of the limitations of using biodiesel fuel for diesel engines is higher cold flow properties compared with petroleum diesel fuel (4). Cold properties consist of cloud point, pour point, and cold filter plugging point. The cloud point is a temperature at which the fuel starts to thicken and cloud, the pour point is a temperature at which the fuel thickens and no longer pours, and the cold filter plugging point is the lowest temperature at which fuel still flows through a specific filter. These... 

Recently, two processes for biodiesel production from crude tall oil have been proposed [48, 49]. They rely on the use of a homogeneous acid catalyst or of an acyl halide for the esterification reaction, but no information was given on the properties of the fuel obtained, particularly concerning the oxidative stability and conformity with European specification EN 14214 2003 for IV. 

The Calculated Cetane Index (CCI), though not an accurate predictor of Cetane Number for biodiesel, since it is based on a calculation using specific gravity and the distillation curve, was used to estimate the Cetane Number of the biodiesel and two diesel fuels. From the results it can be seen that biodiesel has a CCI value higher (55) than that of diesel No.2 (49). This accords the biodiesel with better cold-start properties, minimizes the formation of white smoke (emissions), and leads to less engine noise and hence improved engine durability and reduced fuel consumption. ... 

The specifications for biodiesel are designed to ensure that consumers will not experience operational problems from the fuel s use. ASTM and European Union have standard specifications designed for BlOO FAME used in biodiesel blending, which include GC (gas chromatographic analysis), elemental analysis, as well as physicochemical properties of the produced biodiesel [3,4]. Quality fuel will provide the consumer with improved air quality and enhanced operability. Poor quality fuel will create operability problems and increased maintenance activity. It is really necessary to look for newer approaches for the production of biodiesel particularly for variable quality feed stock employing nonedible oils or used flying oils. 

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