How Biodiesel Is Made Into Fuel
You stop at the service station and fill up your diesel vehicle. As you are reading the pump you notice that it says biodiesel has been mixed in with your diesel fuel. That gets you to wondering. What exactly is biodiesel and how is it made? Making biodiesel is a rather simple process and requires very few ingredients, vegetable oil being the primary raw ingredient. It is so simple to make that many people have taken to making their own biodiesel at home. This is how biodiesel is made.
1. The first step is to acquire the raw material that is going to be transformed into biodiesel. This can be any virgin or used vegetable oil. Most large scale biodiesel operations use either soybean or rapeseed oil. Soybean oil is preferred because the leftover protein from the soybeans after the oil has been removed can be sold as a food source for people or animals. Used cooking oil is a suitable alternative for a smaller scale operation.
2. After the the raw material is obtained it is run through a filter system. The type of filter will depend upon the source of the oil. Used cooking oil will require a lot more filtering than will a virgin oil. All particles must be removed from the oil.
3. After filtering, the next step is to remove as much water as possible from the oil. The oil is slowly heated to a temperature above the boiling point of water. It is held there for a length of time until all of the water has been boiled off.
4. The next step is where the oil is actually transformed into biodiesel. A chemical known as sodium methoxide, a mixture of methanol and lye, is added to the oil in the proper proportions and allowed to sit until the chemical process has completed.
5. At this point what is left is now a mixture of esters created from the oil, this is the biodiesel, and glycerin. It is allowed to sit until it separates and the glycerin is drained off. The glycerin is sold to soap and cosmetic companies. What is left is biodiesel.
6. The biodiesel is now put through a process known as washing which will remove any impurities that may still remain. After the biodiesel is cleaned it is dried one more time, driving off any remaining water.
7. It now ready for use. It can be used as is in most diesel engines without any changes to the engine. In most cases it is mixed with petroleum based diesel fuel and sold as a blend. Check with the manufacturer of your vehicle to see which blend they recommend for your vehicle.
As you can see, biodiesel is produced in a very simple process with very little waste. There are kits available if you would like to try to make your own biodiesel at home. If you choose to try to make your own biodiesel make sure that you get proper instructions and always follow proper safety precautions.