Recovery of biodiesel |
|
|---|---|
| Pour the contents of the flask into separating funnel and let stand for 30 minutes. |
|
| The mixture separates into layers. The glycerol from the vegetable oil sinks to the bottom while the biodiesel floats on top. Pour out the glycerol. Collect the biodiesel. |
|
| Ask your teacher to give you further instructions of what to do with the biodiesel you have collected. You may demonstrate the biodiesel acting as a fuel by placing it in a kerosene burner as shown on the right. |  |
| The fatty acids in the vegetable oil are present in the form of triglycerides. What are triglycerides? | |
| Where does the glycerol come from? | |
| What is transesterification? | |
| Can you explain why the biodiesel melts at a lower temperature than the vegetable oil? | |
| Why is it important that the biodiesel have a low melting temperature? | |
| Biodiesel is intended to replace petrodiesel as a fuel in Diesel engines. A common question is why not just use the natural vegetable oil , rather than going to the trouble to convert it into biodiesel. After all, the original diesel engine, designed by Rudolf Diesel, was intended to run on pure vegetable oil. Research and explain. *Consider viscosity and the injection pumps used by modern vehicles. |
|
| Diesel engines are referred to as “compression ignition” engines. What is a compression engine? What is the difference between how diesel is ignited and how normal petrol is ignited in a car engine? |
|
| If care is not taken with the quantities of reactants soap is formed. What are the similarities between soap and the formation of biodiesel through transesterification? Research . | |
| Continue with questions for senior Chemistry | |
| Continue with an investigation of the heat of combustion of your biofuel | |
