Biodiesel

This project is sponsored in part by the USDA National Biodiesel Education Program
biodiesel processes utilize a 6 to 1 molar ratio of alcohol to oilwhich is an excess of 100%, in order to drive the reaction to completion. Most of the excess alcohol (up to 60%) will end up in the glycerol layer after the reaction. Larger scale biodiesel producers refine their crude glycerol and move it to marketsin the food, pharmaceutical, and cosmetic industries. It is generally treated and refined through filtration, chemical additions, and fractional vacuum distillation to yield various commercial grades, such as dynamite grade, yellow distilled, and chemically pure as well as grades established by the United States Pharmacopeia (USP). As more and more crude glycerol is generated, researchers arestuding economical ways to utilize it, thus further defraying the cost of biodiesel production. This article reports the characterization of crude glycerol obtained when biodiesel was produced from mustard, rapeseed, canola, crambe, soybean, and waste cooking oils. Analytical tests were conducted on the parent oils and on the crude glycerol as it was recovered after separation from the fuel withoutfurther processing. Measurements included fatty acid profile, viscosity, heat of combustion, macro elements, carbon and nitrogen content, and food nutrient analysis. Although not shown here, the fatty acid profile analyses on the vegetable oils showed that each of the oils is dominated by three or four of the fatty acids. Canola, soybean, and WVO oils concentrated more heavily on the shorter chainmolecules while the mustard, rapeseed, and crambe oils shift toward the longer, heavier ones, particulary erucic acid. Table 1 shows the analytical results from the macro element screening tests. As expected, the carbon and nitrogen levels in both the oil and the glycerol samples were very homogeneous with the carbon at about 77% in the oil and about 25% in the glycerol, and nitrogen at 0.22% and 0.05%respecSoybean Crambe WVO

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Characterization of Crude Glycerol from Biodiesel Production from Multiple Feedstocks
Biodiesel production worldwide has been on an exponential growth curve over the past several years. The principal by-product of this production is glycerol, also known as glycerin. It occurs in vegetable oils at a level of approximately ten percent by weight. For eachgallon of biodiesel produced, approximately 0.35 kg (0.76 lb) of crude glycerol is also produced. This crude glycerol possesses very low value because of its impurities. As the production of biodiesel grows, the quantity of crude glycerol generated will be considerable, and its utilization will become an urgent topic. The make-up of crude glycerol varies depending on the parent feedstock and thebiodiesel production process. Before the crude glycerol can be considered for possible value-added products, it is necessary to characterize the crude glycerol for its physical, chemical, and nutritional properties. Most industrial
Feedstocks IdaGold Mustard 2.7 +/- 0.2 BDL 0.8+/- 0.0 BDL 26.0 +/- 2.2 BDL 77.3 +/- 0.58 0.22 +/- 0.03 11.7 +/- 2.9 BDL 3.9 +/- 1.0 25.3 +/- 1.2 21.0 +/- 2.9 1.17 +/- 0.1524.0 +/- 0.00 0.04 +/- 0.02 PacGold Mustard 4.9 +/-0.5 BDL 1.3 +/- 0.1 8.0 +/- 0.9 23.0 +/- 1.5 BDL 77.0 +/- 0.00 0.21 +/- 0.02 23.0 +/- 1.0 BDL 6.6 +/- 0.4 48.0 +/- 2.0 16.0 +/- 1.4 1.23 +/- 0.12 24.3 +/- 0.58 0.04 +/- 0.01 Rapeseed Canola

Measurements on oils
Calcium, ppm Potassium, ppm Manesium, ppm Phosphorus, ppm Sulfur, ppm Sodium, %wt Carbon,%wt Nitrogen, %wt

15.7+/- 0.6 BDL 2.1 +/- 0.113.0 +/- 0.9 24.0 +/- 1.1 BDL 77.3 +/- 0.58 0.17 +/- 0.12 24.0 +/- 1.7 BDL 4.0 +/- 0.3 65.0 +/- 2.0 21.0 +/- 1.0 1.06 +/- 0.07 25.3 +/- 0.58 0.05 +/- 0.01

7.6+/-0.9 BDL 1.6 +/- 0.0 10.0 +/- 0.8 22.0 +/- 1.8 BDL 77.0 +/- 0.00 0.22 +/- 0.01 19.7 +/- 1.5 BDL 5.4 +/- 0.4 58.7 +/- 6.8 14.0 +/- 1.5 1.07 +/- 0.12 26.3 +/- 0.58 0.05 +/- 0.01

3.1 +/- 0.2 BDL 1.2 +/- 0.1 10.0 +/- 0.9 22.0 +/- 0.6 BDL...