Note: The following procedure is for synthesizing a biodiesel mini-batch from 100% pure unused vegetable oil. This method can easily be modified for using recycled, used vegetable oil. For more on this, see the endnotes.

1. Warm up 10 mL of 100% pure vegetable oil to about 40°C in a 100 mL beaker. Warming the oil up is not necessary, but increases the reaction rate. 

2. Transfer 2ml of Sodium methoxide solution (be sure the solution is well mixed – should appear cloudy) to a 50ml beaker with a magnetic stirrer.  Stirring gently, add 10ml of warm oil.   Cover with watch glass and turn up stirrer to position 7 or 8.  Stir for about 30 minutes. 

3. Transfer the contents of the beaker into a 15 mL plastic centrifuge tube. The mixture will separate into two different layers. The glycerol will fall to the bottom, and the methyl ester (biodiesel) will float to the top. Since about 75% of the separation occurs within the first hour, you will be able to see immediate progress. Allow the experiment to sit for about an hour. 

4. Using a transfer pipet, carefully draw off the top layer of biodiesel. Make sure not to get glycerol (bottom darker layer) in the biodiesel. 

6. Use the IR spectrometer to identify your products. Print out the spectras and compare with known spectra. The biodiesel may be hard to compare, since most oils are comprised of different length carbon chains. Comparing to known spectra can easily identify the glycerol. The presence of glycerol indicates a successful reaction.