| dc.description.abstract | Worldwide concerns about fossil fuel depletion and energy security have recently
triggered a research interest in biodiesel, which is renewable, biodegradable, and has
several other advantages as an alternative to petro diesel. However, biodiesel may cause
engine problems, especially fuel filter plugging, associated with its use in cold weather
conditions. Trace contaminants such as glycerin, saturated monoglycerides (SMG), and
soap compromise cold weather performance of biodiesel. A cold soak filtration test was
recently included in the U.S. specifications for biodiesel (ASTM D 6751-09) to evaluate
biodiesel cold weather performance.
Canola seed has good potential to be a locally important biodiesel feedstock
because of its high yield (1500 to 2200 kg/ha) and oil content (40 to 50%, Brassica napus
L.), as well as a suitable fatty acid profile for good cold weather performance. For a plant
breeding program evaluating canola biodiesel quality traits, rapid preparation of biodiesel
samples and assessment of its quality is important. In this work, an in situ alkaline
transesterification method was adopted for preparing canola biodiesel. It was found that the
biodiesel yield via this method was improved by reducing seed moisture from 6.7% to 0%
after oven-drying. The resulting biodiesel had qualities comparable to or better than
biodiesel prepared through the conventional alkaline transesterification.
Only a limited amount of seed from new canola lines is typically available in a
plant breeding program; obtaining the required volume of biodiesel for evaluating cold
soak filterability (300 mL) is not possible. In order to rapidly screen canola breeding lines for B 100 quality, cold soak filterability must be assessed with reduced volumes of
biodiesel. Therefore, this study evaluated the impact of SMG, glycerin, and soap on cold
soak filterability. Biodiesel filtration time rapidly increased to unacceptable levels and
became much less reproducible when the SMG concentration was raised above 0.28%. A
regression model was generated to predict the filterability of biodiesel against the
concentrations of trace contaminants. A downscaled model of the filtration test with a
reduced volume of biodiesel sample (25 mL) was also tested and calibrated.
The in situ transesterification method saved 30% operator time compared with the
conventional method. By combining the downscaled cold soak filtration test, the goal of
analyzing 40 biodiesel samples/wk was achieved. | en_US |
