As pollution from automobiles and energy production takes their toll on our environment, strides have been made to seek more renewable and environmentally safe forms of fuel and energy. One such push for renewability is the use and production of biodiesel. Compared to our current source of fuel which is finite and gradually declining, biodiesel is a large step towards a near 100% renewable fuel source. Most biodiesels are made from oils from vegetables such as soybeans or corn but, as seen in our experiment, waste cooking oils can also be used to make biodiesel.
There are two main parts in our biodiesel refining experiment, the first step is to titrate the oil being refined so that the amount of base required to neutralize the oil can be determined, the second step is to use the data we collected from step one to refine the waste oil into biodiesel. For a specific sample of oil, the amount of base required to neutralize a gram of oil would have to be calculated. Using our calculations, the required amount of base was added to methanol, this depends on the amount of oil that is being refined. The methanol-base solution is added to the oil and heated. After heating the solution is placed into a sep funnel and allowed to separate. The two resulting layers are glycerin on the bottom and our biodiesel on the top. The biodiesel was extracted, heated again, and our biodiesel is finished. Additionally, the heat of combustion of the refined biodiesel was tested via calorimetry.
The most interesting result of our biodiesel refining experiment was the effectiveness of the biodiesel product. The purpose of biodiesel is to replace current finite fuels with one that is renewable but if biodiesel does not perform to the same standards as current fuel, then it may not be used as a replacement. However, from the results of our calorimetry testing, the refined biodiesel has a greater heat of combustion (53.21 kJ/g) compared to fuel used today such as octane (48.23 kJ/g). These results show that it is likely that one-day modern fuels will be replaced with biodiesels which is a good step towards a renewable and hopefully cleaner future.