Intro to making biodiesel yourself

Safety and precautions legal disclaimer, must read!
First, making biodiesel is a potentially hazardous activity.  You are handling and working with chemicals that could seriously injure you, kill you, and even cause a fire and burn down your house and your neighbor's houses.  When handling biodiesel making chemicals, always wear full protective chemical resistant clothing and goggles/face shields and have multiple fire extinguishers with appropriate classes available located in easily accessible locations.  Always work in a well ventilated area, as poisonous gases are created when making biodiesel and mixing biodiesel related chemicals, and away from any persons and/or property.  Always check with the local, state, and federal fire marshals to verify your compliance with all applicable fire regulations and codes at all times with all materials, usage, and methods, and anything else not mentioned here that may be related to biodiesel, biodiesel making, or biodiesel storage.  If you have any doubt about the safety of making biodiesel, or do not know how to make it safely, do not attempt to make biodiesel or work with biodiesel-related chemicals unless you have complied with all of the above precautions and any other commonly prescribed precautions when working with biodiesel and biodiesel making chemicals and processes.  Lastly, using biodiesel may void your car's warranty and may be subject to road taxes, check with your car manufacturer and lawmakers to find out for sure before using or making biodiesel.  

While most biodiesel has a higher flash point and is more resistant to open flame than diesel fuel and significantly more resistant to open flames than gasoline, it can still be ignited.  Some other fire hazards when making biodiesel are heat sources such as open burners, pilot lights, and electrical wiring.  Open housings for electric motors may also expose brushes inside the motor which causes sparks.  Pulling or pushing electrical plugs or faulty electrical switches could also create a spark.  Proper ventilation and using an air tight reaction chamber will greatly reduce the chance of fires or ignition of flammable gasses.

The chemicals you will most likely use are methanol, or wood alcohol, a main ingredient in barbeque lighter fluid or model airplane fuel.  Methanol cannot be filtered by any respirator cartridge filter, you must have it under a fume hood or have a clean air supply when handling.  Lye, or sodium hydroxide, is a main ingredient in drain or stove cleaner.  Ethanol is a type of alcohol, the type of alcohol found in grain alcohol, vodka, gin, etc.  Each of these ingredients on its own or mixed with each other can be a fire hazard and can be poisonous in sufficient quantities.  Take all safety precautions when handling, transporting, mixing, and/or in any way working with or using these chemicals.  

While there is risk when dealing with biodiesel, biodiesel-related chemicals, and it's production and storage, most people are able to safely handle these chemicals in a safe and competent manner after proper instruction.  The chemistry is only high school level and you already have similar chemicals in your liquor cabinet, under your sink, and in your french fries.  However, if you are sloppy, not consistent, don't do your research, and/or don't follow safety precautions, making biodiesel yourself can be dangerous so do not attempt it in these cases.  There is potential danger in many everyday items, like using drano as shampoo or a loaded handgun as a hammer, so please educate yourself on how to properly use and safely handle them!  Again, most people can safely and competently make biodiesel but seek guidance in addition to the information linked below.  See the additional legal disclaimer in the Terms of Service Agreement.

Introduction to making biodiesel

Here is a general introduction to making biodiesel.  Biodiesel is less toxic by mass than table salt and degrades quickly if spilled.  It also has a higher flash point than petrol diesel which makes it safer to handle than petrol diesel.  It is significantly more resistant to an open flame than gasoline.  Local restaurants will normally give you their waste oil for free, so the only cost is for set-up materials, chemicals, and your time.  This is all in addition to the fact that biodiesel provides enhanced lubricity to the engine and is a greener fuel with reduced emissions compared to petrol diesel.

Biodiesel is made at home by taking heated and filtered oil, and then mixing measured quantities of required chemicals for the reaction with the oil.  The chemicals used are a catalyst, usually NaOH, or KOH, and methanol.  After mixing the chemicals in a specific order and letting the products settle, you drain the waste products off the bottom and then wash with water or bubbles to remove any impurities.  Then, let it dry to remove any residual water and you're done!

The chemical process is high school level chemistry that can be done by almost anyone.  The oil, which is mostly triglycerides, is reacted and produces ethyl esters and glycerol.  The alcohol serves as a catalyst and you heat the whole thing to add energy to the reaction.  The most complicated part is figuring out how much of each chemical you need.  This is done in a process called titration, where you take an oil sample and add 1 drop of a lye solution at a time.  You count how many drops, or mL it takes to turn the sample pink, and this tells you how much lye was needed to react the sample.  Some quick math then tells you how much lye you need for the rest of your batch.  It has to be done each batch because each batch may require different levels of chemicals to react properly and completely.  Note - these are not detailed directions on how to make biodiesel, do your own detailed research before attempting to make biodiesel!

A conservative approach would start with small quantities of biodiesel made with clean, unused oil, to test the process and practice.  Make sure you read, re-read, and comply with all safety precautions and practices!  After you practice making biodiesel in small quantities, you can start to think about setting up a larger processor, anywhere from 20 to 100 gallons, and making it in larger quantities. 

Refer to these pages below for specific steps in making small batches, larger batch processing, biodiesel processor plans, titration, chemicals, etc.  These websites also have other advanced topics available.  Read ALL safety links, and become familiar with all steps and seek further guidance before attempting to make biodiesel.  

Biodiesel safety: must read


Titrating oil


Making small batches


Drying biodiesel


Basic processor plans


Advanced processor plans


Other useful links blog and forum on how to make biodiesel biodiesel forum Maria "Mark" Alovert's biodiesel making book and website biodiesel standards Iowa state university biodiesel home page  the official site of the national biodiesel board biodiesel parts supply seller, has "how to" videos and MSDS (Material Safety Data Sheets) for various chemicals involved in making biodiesel wikipedia biodiesel article wikipedia petro diesel article



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