1. Alexis Aberle CBE 555 Spring 2008
Biodiesel Fuel
Alexis Aberle
CBE 555
Spring 2008

2. Definition
Biofuel: Fuel made from biological ingredients instead of fossil fuels
Starting ingredients range from corn to soybeans to animal fat
Non-toxic and renewable
Is usually blended with pure diesel
Numbering system: B20 is most common, meaning the fuel is 20% biodiesel
A fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, designated B100, and meeting the requirements of ASTM D 6751 (National Biodiesel Board)

3. History of biodiesel
Transesterification of vegetable oil before first engine, in 1853 by E. Duffy and J. Patrick
Rudolf Diesel
1900 World’s Exhibition in Paris
Engine ran on peanut oil, the world’s first biodiesel
Used until the 1920’s when petroleum diesel more common due to superior pricing

4. Plant oil is the largest source
Soybean
Rapeseed
Canola
Palm
Cottonseed
Sunflower
Peanut
Why? These compounds contain triacylglycerols, or fat
C63 H12 2O6

5. Abbreviated process Transesterification
Fat or oil is first purified then reacted with an alcohol, usually methanol or ethanol
Sodium or potassium hydroxide is used as a catalyst
The triacylglycerol is then transformed into esters and glycerol
Remaining esters are biodiesel

6. Block Flow Diagram
Oils and fats are preprocessed to remove water and contaminants
Pretreatment removes FFA
Oils and fats are mixed with an alcohol and catalyst
Triglycerides are broken apart and reformed into methyl esters and glycerin
Separated and purified

8. Titration
Why? To find out how much catalyst is needed, since oil will first react with lye to make soap before desired reaction, biodiesel, can occur
Reaction is complete at pH of 8.5 – use phenol red
Lye/free fatty acid reaction
Every 1 mL titration will tell you to add an extra gram of lye for each liter of oil/ffa to compensate for the side reaction

9. Washing process Unwashed biodiesel contains soap
If mixed, the water, soap, and biodiesel will form an emulsion – takes longer to separate
Perform washes by adding water, GENTLY mixing, and decanting water
As number of washes increases, will be able to mix more vigorously
Washing is complete when water is clear

10. Glycerin Every gallon of biodiesel produces a pound of glycerol
Settling stage of production: mix of glycerin, methanol, lye catalyst, soap
Phosphoric acid
precipitates out the catalyst
Converts soap back to FFA
95% pure
Hard to purify: BP 290 °C

11. Soap Need to remove methanol Saponify: better cleaner
Simple condenser recovers methanol
Saponify: better cleaner
Add lye and water, heat, set for 2 weeks
NaOH: Solid soap; KOH: Liquid soap

12. Pros Environmentally friendly Can help reduce dependence on oil
Helps lubricate the engine, reducing wear
Can be used in virtually any diesel operating vehicle
Safer than conventional diesel
Fewer emissions, biodegradable, renewable
Is the only biofuel that has successively completed emissions testing in accordance with the Clean Air Act
Non-toxic

13. Reduced emissions
Emission Component
B100
B20
Total Unburned Hydrocarbons
-67%
-20%
Carbon Monoxide
-48%
-12%
Particulate matter
-47%
NOx
+10%
+2%
Sulfates
-100%
PAH
-80%
-13%
Additionally, B100 can also reduce CO2 emissions by 78% and lower carcinogenic properties of diesel fuel by 94%
Degrades at rate of four times faster than standard diesel fuel

14. Cons
Unfortunately, when the particulate matter is decreased, there is a corresponding increase in NOx emissions, contributing to smog formation
Because it acts as solvent and loosens things, it can clog fuel filters
Breaks down rubber components – fuel lines and fuel pump seals usually constructed of this
1.1 gallons biodiesel equals 1 gallon standard diesel – 10% reduction in energy efficiency

15. Corn vs Soybean More fertilizer and pesticides required for corn
Corn and soybean produce 25% and 93% more energy than consumed, respectively
420 gallons ethanol per acre for corn and 60 gallons per acre for soybeans

16. Algae? How? Aquaflow in New Zealand
Grow colonies in presence of sunlight
Starve them of nitrogen
Filter out cell membranes and organelles
Solvent to separate out the fats
Purify fats, evaporate solvent
Aquaflow in New Zealand
Cold pressing: how oil is retrieved from plants
140 billion gallons of biodiesel every year
Soybeans: 3 billion acres
Canola: 1 billion acres
Algae: 95 million acres – only would need about size of Maryland

17. Glycerin By-Product Uses
Composting: Must be in hot environment; releases sulfates
Soaps
Nitration: produces nitroglycerin
Ascanio Sobrero discoverer 150 years ago
Alfred Nobel: Nitroglycerin + Silica: Dynamite!
Heart disease drug: 0.6 mg
Sweetener
Health supplement
Preserving plants
Cosmetics
Current research underway to use for fighting weeds and growing grass

18. Biofuel home heating Massachusetts: 36% of homes heat with oil
New bill: must contain at least 5% of biofuel by 2013, increased from 2% by 2010
Cellulosic ethanol not available for about three years

19. Concerns Operate in cold weather? Solution
Biodiesel can gel when it gets cold
Solution
Blend with standard diesel: B20 is operates well in cold climate
Additives:
Pour point depressants
Filterability or flow improvers that lower CFPP
Wax anti-settling additives
Must be introduced in the fuel before it reaches cloud point and properly blended
Block and filter heaters
Blend with kerosene
Excellent cold flow properties

20. Production in the US
Production currently is small but tripled from 2004 to 2005 and again from 2005 to 2006.
Soy is the driving force for this industry
Potential saturation of the market for glycerin could limit the growth
75 M gallons per year total; largest market fleet vehicles
Potential future targets: marine and agricultural applications and home heating

21. Global Production In 2005, 3.8 million tons produced
85% from European Nation
United States: 8%
Rest of World: 7%
Cost to produce varies considerably, from $0.29 per liter to $9.00 per liter

22. Questions?
Conflicting data: 4.5 M vs 95 M acres of land for production of algae for transportation needs
Biofuel: 10% energy reduction vs 8% energy reduction from diesel; also some say production process uses more energy to make than it than what you get out
Increased production of corn and soybeans: less valuable for farmers?

23. References http://www.pacfuel.com/historybd.htm
Cunningham, Aimee. "Farm-Fuel Feedback." Science news (2006): 36-7.
Svoboda, Elizabeth. "The Fuel Cell." Popular Science (2007):
Thurmond, Will. "Biodiesel's Bright Future." Futurist 41.4 (2007):
Rosner, Hillary. “Coking up more uses for the leftovers of biofuel production.” New York Times 8 Aug