How to Make Lauric Acid

Coconuts are one of the two main commercial sources of lauric acid.

Lauric acid is the common name of a saturated fatty acid that is officially called dodecanoic acid for its backbone of 12 carbon atoms. Like practically all fatty acids, it has a methyl group (-CH3) at on end and a carboxyl group (-COOH) at the other. Between these lie 10 saturated -CH2- groups, hence the formula CH3(CH2)10COOH.



Lauric acid is one of the most common fatty acids in nature. It is especially common in cinnamon oil, coconut oil and palm kernel oil. The last two crops provide nearly all the free lauric acid on the market, but it is possible to synthesize it in a lab.

Things You'll Need

• Lauronitrile, CH3(CH2)10CN
• Concentrated hydrochloric acid, HCl
• Proprionic acid, CH3CH2COOH
• Baking soda
• Beaker, 500 mL
• Flask, 500 mL
• Glass stopper
• Microwave oven
• Oven mitt
• Filter paper

Instructions

1. Place 18.1 grams (0.10 mol) of lauronitrile in the flask.

2. Mix 100 mL of concentrated hydrochloric acid and 200 mL of propionic acid in the beaker and pour the solution into the flask.

3. Seal the flask with the glass stopper and swirl the contents to thoroughly combine them.

4. Place the sealed flask in the microwave oven and microwave on high for 10 minutes.

5. Put on the oven mitt and remove the flask from the microwave oven. Let it cool.

6. Remove the stopper from the flask. Add to the flask 132 grams of baking soda (sodium bicarbonate) to neutralize the acids. The reaction will fizz and release carbon dioxide.

7. Wash out the flask with water and filter the contents through the filter paper. Lauric acid and lauronitrile are practically insoluble in water, but the acids and baking soda, and their reaction products, are. Wash the material left on the filter paper. The final product is mostly lauric acid, but it is not pure.

Tips & Warnings

• Acids burn, so be careful.

• Do not use the lauric acid you've produced. It is not pure and may be tainted with potentially harmful chemicals.

References

• AOCS Lipid Library: Production of Unusual Fatty Acids In Plants
• Cyberlipid Center: Fatty Acids
• Chemical Book
• "Journal of Radioanalytical and Nuclear Chemistry"; Facile conversion of [1-14C]lauronitrile to [1-14C]lauric acid under microwave irradiation; K. M. Mathew and S. Ravi; Volume 267, Number 1, 245-246; 2006