How to Make Biodiesel:-

The following steps illustrates how to make this biodiesel:-

1. Purchase or collect new or used vegetable oil.

2. If the oil is used cooking oil, use a restaurant fryer filter to remove burned food bits, etc.

3. Purchase some methanol alcohol from a local racetrack or chemical supply store. Ethanol alcohol can also be used, but the process is different.

4. Purchase some granulated lye  or caustic soda sold as a drain cleaner from the hardware or grocery store. It must be pure sodium hydroxide (NaOH).

5. Measure the amount of vegetable oil you want to use in liters. We will call this number V. Pour the vegetable oil into the mixing container.

6. When the temperature is below 70°F (21°C), or when the vegetable oil is solid or lumpy, it will be necessary to heat the reactants before, during, and possibly after the mixing. The ideal temperature to attain is 120°F (49°C). A fish tank heater will heat 10 to 30 gallons (40–120 l) of reactants. For larger batches of biodiesel, a water heater element can be mounted in a steel biodiesel mixing tank. 

7. Multiply V x 0.2. The result will be the amount of methanol you will need in liters.

8. To determine how much lye you will need to use for new vegetable oil, multiply V times 3.5 

grams. For used vegetable oil, use the number of grams of lye you got in the small test batch. For example, if you used 0.55 grams of lye in the test batch, you will multiply V times 5.5 grams of lye. Call this number L.

9. Carefully pour L grams of lye into M liters of methanol. Stir until the lye is dissolved in the
methanol. Be careful, this creates a toxic substance called sodium methoxide.

10. Pour the sodium methoxide into the vegetable oil right away. Stir vigorously for one hour.

11. Let the mixture settle for eight hours.

12. Pump the biodiesel from the top, or siphon it off with a hand siphon. Or if you are lucky 

enough to have a container with a spigot, open the spigot and drain the bottom layer of glycerin. The glycerin will be much thicker and darker than the top layer of biodiesel.

13. Allow the glycerin to sit in the sun for a week. After that, the trace methanol will be evaporated. You have made a nice glycerin soap. You can scent it with the fragrance of your choice, add other soap agents as desired, or just use it as it is.

14. Make sure your biodiesel goes through a 5 micron filter before entering your diesel engine.