'A Comparison of Some Test Methods for the Evaluation of Biodiesel Quality and Blends.'

摘要

There is a need for improved rapid inexpensive test methods to evaluate biodiesel. This presentation describes the results of testing biodiesel samples and blends using several test methods including less expensive quick test methods. The study involved analysis of some 26 commercial samples and laboratory production samples of biodiesel. By definition, biodiesel requires passing ASTM D6751 but many small producers and "backyard" brewers have a need for quick methods to assess their fuel quality. Test methods used in this study included ASTM D6751 tests for glycerides and methanol (D-6584), acid number (D-664), and cloud and pour point (D2500, D97) and the methanol solubility and pHLip "quick tests", QTA infrared, I-Spec Impedence Spectroscopy, Fourier Transfer Infrared (FTIR) and preliminary assessments of Thin Layer Chromatography. In some states use of low level blends of biodiesel are mandated and accurate methods to assess blend level are needed. Results of a study of some 100 biodiesel blends are reported. Blend levels were evaluated using viscosity and FTIR. Some preliminary assessments of biodiesel blends were conducted using a modified I-Spec hand held unit. In general, all tests have some merit but to insure biodiesel quality, ASTM D6751-09, BQ9000, or EN 14214 are required.