Optimising Process Control and Screening Finished Product

ESA Biosciences Inc. (USA) has developed two new HPLC-Corona charged aerosol detector applications for the Biodiesel industry. The first analyzes incoming oils for fatty acids and bound glycerides. This same method can be used for monitoring the efficiency of reaction in the various stages of the biodiesel manufacturing process. The second method provides quantitative results for both free and bound glycerides, yielding total glycerides values without the need for high temperature GC.

Using reversed-phase HPLC and the Corona detector, method one provides information needed to optimise the chemical process for transforming raw oils into finished biodiesel product. It can also be used to qualify incoming oils before they are used in the manufacturing process. In-process samples can be analysed to confirm that each step is complete before continuing on to the next step in the process. The result is a more efficient manufacturing process and a higher quality finished product.   The second method utilizes the same versatile Corona detector with normal-phase chromatography to quantify mono-, di-, and tri-acylglycerides, as well as free glycerol in a single analysis.  Sample preparation is simplified to just a dilution, avoiding derivatisation, expensive internal standards, and unpleasant solvents. This method is used to analyze compounds after the transesterification step. Total glycerol results for B100 biodiesel are comparable to those obtained from ASTM D6587 without the cost and difficulty of the ASTM method.   The Corona charged aerosol detector offers many advantages over other HPLC detection methods (UV, ELSD, CLND, and GC-MS) that historically have been used for these types of analyses. These include low-nanogram sensitivity, a dynamic range exceeding four orders of magnitude and good precision response factors that are independent of structure. The ideal complement to UV detection, Corona provides HPLC detection of non-volatile and many semi-volatile compounds and is a robust, reliable, plug-and-play device requiring minimal training to operate.