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Making your own bio-diesel

  1. Jan 11, 2012 #1
    Hi All,

    New to the forums and fascinated with chemisty, physics and engineering.

    Two years ago i bought a 250 acre rural property and live about 45mins from a major town where i work.

    With fuel prices going up and up and other economic turmoil, i've decided to put my property to good use and to start researching how to make my own bio diesel.

    I did do a search on the forum before i started this post, but couldn't find such a topic.

    From the basic research i've done, you can make your own bio-diesel using:

    80% Vegetable oil
    19.65% Methanol
    0.35% Lye

    To make the whole process cost effective, i would need to manufacture the methanol and vegetable oil (or get it from McDonalds).

    (Edit: link deleted)

    The questions i have are.

    1) How do you cost effectively make methanol?
    2) Can you use ethanol instead of methanol to make bio-diesel?

    Any good links or info on this would be hugely appreciated.

    Kind regards,
    Last edited by a moderator: Jan 11, 2012
  2. jcsd
  3. Jan 14, 2012 #2


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    You won't be able to make methanol any cheaper than you can buy it. The low tech way to make it is by destructive distillation which is very hazardous unless you know what you're doing and if you do it to scale will likely attract a lot of attention. Yield is fairly low and lots of bad chemicals are produced as well which will cost to dispose of or flare properly. Big bucks. Current pricing is about $1.10/gal when you buy a ton so you might buy in quantity to get the best price. You will not be able to make it any cheaper than that but if you find a way, give up your day job and become a multimillionare with your process. You will likely find that suppliers won't sell large quantities to you unless they think you know what you're doing. Most won't sell to individuals, even if you know what you're doing, so it is better to form a company.

    Ethanol, however, is dead easy. Ferment something sweet and you're off to the races. It will require a large still, which will make you 'interesting' to certain state and federal agencies, but you can do it. The final distillation to remove the last traces of water will be tricky and will require some special equipment and materials but it can be done. Price for this is horrible though... even more than methanol unless you can get the sugars and fuel/energy for practically nothing. The biodiesel produced with ethanol has higher cloud points and viscosity so it will be 'interesting' to work with.

    So, what I've found is that you have to buy your methanol, sodium methoxide (or sodium hydroxide and make your own) and your used veggie oil. Almost gone are the days when you could go down to the local restaurant or donut shop (the best oil, I've heard) and pick up the waste for practically nothing, at least legally that is. I would be totally shocked if you could get McDonalds to let you touch it but YMMV. Focus on the donut shops! Biodiesel will cost you more than petro diesel sometimes and it's WORK to do it properly. The cost of waste disposal is a factor as well. You will use a lot of water and generate a lot of caustic waste or perhaps acidic waste if you first treat with strong sulfuric acid. Some folks don't bother with calculating waste costs and simply dump the waste into the sewer. If you try that, expect fines and scrutiny from the wastewater district. They can find you, BTW. Since the byproducts really impact the wastewater's FOG, BOD and COD numbers, they put an end to it (disposal down the sewer) if you get to producing large scale. If you intend to just broadcast it over your land or use your own septic system, you'll probably be alright. Just neutralize your waste before releasing it.

    You'll find that making your own oil is a real pain but low tech methods might be cost effective if you don't figure your own labor.

    I'm interested to hear about your small scale oil production ideas.
  4. Jan 29, 2012 #3
    Thanks so much for your response. You have given me a lot to consider, not to mention the viability of purchasing methanol.

    Refining and producing a near pure ethanol doesn't sounds seem to be a viable option based on the research i've undertaken.

    I might put this project on hold for the time being.
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