Biodiesel is an alternative fuel for diesel engines, and is made from vegetable oil and/or animal fat and a number of chemicals. Because it is obtained from organic residual material and has proven to reduce harmful emissions when burned compared to conventional fuels, biodiesel has received wide attention as a more or less 'green' source of energy. Here you will find steps to make this fuel yourself.
Method 1 of 2: Preparation
Step 1. Work in a safe environment
This means that you work from a laboratory. You won't find these everywhere, but if you have access to them, you can try to find space at a university or maybe a school. Don't do this at home! The chemicals methanol and lye are far too dangerous to experiment with at home. Also find out whether making your own biodiesel is legal, also because there is a very high fire and explosion risk.
A good working environment is well ventilated and there is access to running water, eye showers, a fire extinguisher, waste containers and a telephone
Step 2. Follow a lab's dress code
Most labs have dress codes that everyone must adhere to. Always wear a long-sleeved shirt, long pants, and shoes in any lab environment.
Always wear a sturdy apron when making biodiesel, chemical resistant gloves (butyl rubber is best when working with methanol and lye), and safety glasses. The gloves should come up to your elbows, or have cuffs that you can pull over your long sleeves
Step 3. Make sure you have a good quality oil
The easiest oils to use in making biodiesel are neutral vegetable oils, such as canola, corn and sunflower oils - these are available at the supermarket and have a low melting point, meaning they will not solidify in a cold environment.
- Avoid peanut, coconut and palm oil, paraffin and pork fat. These species already solidify at room temperature. Biodiesel usually has a lower melting point than the oil it is made from, but it is better to avoid these types of oil, especially if you are a beginner.
- Also, do not use olive oil. Like peanut and palm oil, paraffin and pork fat, olive oil contains more acids than the recommended neutral oils. These acids can disrupt the reactions needed to make biodiesel.
- It is also possible to reuse vegetable oil that has already been used for cooking to make biodiesel. This oil must of course first be filtered to remove small contaminants, after which you leave it for 24 hours to separate the oil from water and impurities. Pure oil is clear and translucent, with no sediment.
Step 4. Make sure you provide all bins with clear labels
Only use these bins for making biodiesel – never use them again for food storage or processing, no matter how well you wash them afterwards.
Method 2 of 2: Procedure
Step 1. Add 200 ml of methanol to a glass blender or mixer
Be careful not to spill or waste anything. Set the blender or mixer to a low setting.
Step 2. Add 3.5 grams of lye to itTry to weigh the lye quickly, as it absorbs moisture from the air. That is also the reason why you should close the container where you store the lye properly.
The reaction between the methanol and the caustic produces sodium methoxide. Sodium methoxide cannot be exposed to air for long as it breaks down with air and moisture
Step 3. Let the lye completely dissolve in the methanol
This process takes about 2 minutes. Continue once the mixture is clear, with no particles remaining.
Again, be careful - the sodium methoxide will break down quickly, so move on to the next step once the lye has completely dissolved
Step 4. Heat 1 liter of vegetable oil to 55°C and add the hot oil to the mixture afterwards
Run the new mixture in the blender for about 20-30 minutes.
The reaction continues and forms two products - biodiesel and glycerine
Step 5. Pour the mixture into a wide-mouth glass container or carafe
Let the mixture rest.
The mixture should now be separated into 2 layers - biodiesel and glycerine. Since biodiesel is less dense than glycerine, the top layer is therefore biodiesel
Step 6. Let the mixture rest for several hours
As soon as the split is complete, it is important to separate the top layer (biodiesel) and the bottom layer.
Separate the top layer from the bottom layer by carefully pouring it out, or by using a pump
Step 7. Properly dispose of the glycerin
The glycerine can be regarded as waste. Check whether glycerin can be considered normal waste – it usually is.
If you don't want to waste the glycerin, see if it can be used on a compost pile to speed up the rate of composting. You can also make soap with it
- Increasing the temperature of the mixture will make the reaction faster. However, if the temperature rises too high, less biodiesel will eventually be formed.
- Use glasses and not plastic containers. Methanol reacts with plastic, which influences the intended reaction. This has an unknown result.
- If a deposit does form at the bottom of your container of biodiesel, make sure that it does not end up in the fuel tank. Filter the biodiesel until the sediment is gone.
- Work in an environment with adequate ventilation. Most universities and research labs have workplaces with hoods designed to minimize the risk of exposure to harmful fumes.
- Work close to a sink with running water.
- Do not bring food or drink into your work environment.
- Lye dissolves skin. Keep a bottle of vinegar handy – in case lye does get on your skin, rinse it off immediately with the vinegar to neutralize the lye. Then rinse with water.
- Keep the work environment free of distractions. Don't even think about making biodiesel with kids or pets around.
- Be very careful with methanol. Methanol is a very dangerous chemical. It is extremely flammable and can ignite or explode from a single spark. In addition, it is highly toxic and can cause blindness if inhaled or swallowed.
- Check whether you can use biodiesel in your car. Biodiesel can damage engines that are not built to run.