Determination of Free and Total Glycerine in Pure Biodiesel (B100) by Gas Chromatography in Compliance with EN14105

Interest in biodiesel as a clean-burning alternative fuel produced from renewable sources such as vegetable oils has increased tremendously over the last few years, mainly because of its reduced environmental impact in comparison with conventional petro-diesel. Biodiesel can be used as a pure fuel or blended at any level with petroleum diesel. For biodiesel to be commercialized as pure biofuel or blending stock for heating and diesel fuels, it must meet a set of requirements as defined in ASTM D6751 and EN 14214 standards. These standards indicate maximum allowable concentrations of contaminants in B100 finished product, along with other chemical-physical properties necessary for safe and satisfactory engine operation.1

One indicator of biodiesel quality is free and bonded glycerine content. Low levels of total glycerine ensure high conversion of the oil, while high levels of glycerine and glycerides can cause injector deposits, clogged fuelling systems and poor cold weather operation. The analysis of glycerine, mono, di and triglycerides by gas chromatography requires a non-discriminative injection system able to transfer both volatile and heavy compounds without discrimination or degradation. This application describes the use of the Thermo Scientific TRACE GC Ultra for the analysis of free and total glycerine according to EN14105.

View Full Article