Bio diesel is not a new concept it has been around for quite some time, it is largely the idea of using oils such as vegetable oil and canola to power a diesel vehicle. This is not really a strange concept since the first diesel engine was not made to run on our modern day fossil fuels, but instead was run on peanut oil. Diesel motors do not require the same refined process that is used with modern cars, this in mind diesel engines are not designed for smooth high powered running either, they are more like the draft horse of engines, and will generally last a lot longer than a normal car motor.
Many people who make bio diesel themselves use either used cooking oils or grow crops of canola, and crush it to get oil. Ideally if you have the acreage to grow a crop of canola this is the best method as you are getting clean oil to begin making bio diesel so no time will be wanted in the process of cleaning it. Although used oil from fish and chip shops is just as effective provided that you clean and drain it properly the end result is just as good.
There are many different methods available for making Bio Diesel, A simple one that I have found uses the following ingredients: used cooking oil, Methanol, Sodium Hydroxide.
Note that the oil must be heated and drained twice to ensure that you have got all of the muck out of it, if you do not take the time to do this you will block up your fuel filters. It is advisable to begin with a test batch of bio diesel, this is easily done by using kitchen scales and a blender, with a ratio of 6 grams of sodium Methoxide to 1 liter of cooking oil. This measurement is only a guide that is why you do a test batch, to find out the exact calculation that will be required to make a larger batch.
Heat the oil, add the Methoxide solution and mix this in the blender, and let the mixture stand to settle. If the test batch is successful you will see that the glycerin has sunk to the bottom of the mix once settled, Glycerine looks black, and sinks to the bottom of the blender, but the bio diesel will be an amberish color and will float to the top.This means you have separated the mixture and changed the molecular structure of the oil, it can never revert back to its original status again.
Once you have your calculations correct you can start mixing larger batches, you will then need to make up a plant for handling larger amounts of oil. There are blue prints of designs all over the internet, they vary in design, just as much as the recipe for bio diesel does! Find one that you feel is easy to make and understand.
On a final note, when you make bio diesel be sure that you always test the oil first as once you have began the process you cant change your formula. So take care to make sure that all of your calculations are correct before trying to make larger batches. When working with Methanol and Sodium Hydroxide be very careful to take safety precautions to protect yourself from burns, or injury.