Wood Ash Titration

The 12 Principles of Green Chemistry guide us to use catalysts to improve the energy and atom efficiency of reactions. The principles also guide us to use renewable feedstocks. In this experiment, we can see how waste from one process can be used productively in another. Specifically, biodiesel can be made from waste vegetable oil, a renewable feedstock that was traditionally discarded by the food preparation industry. To prepare biodiesel from the vegetable oil, a base is needed as a catalyst. In this lab, we will focus on the catalyst and its source from another “waste material” – wood ash.

Wood ash has been used as a valuable source of base throughout history. In this experiment we will extract the basic substances from a sample of wood ash and then determine their base potential compared to sodium hydroxide, the base often used in the production of biodiesel.

Traditional soapmaking requires “dripping the lye” from wood ash. This same technique has been applied to the production of biodiesel. For more information, you might consult:

http://journeytoforever.org/biodiesel_mike.html