How 2 Make Bio-Diesel FUEL

from autodidactics.com

The manufacture of bio-diesel fuels (Methyl-esters through Transesterification) is just catching on. It is a very simple process and can be done by anyone with a little room, some protective gear, some waste vegetable oil (WVO) or even fresh vegetable oil, and a couple of minor chemicals (Methanol and lye). Methanol is wood alcohol, which can be absorbed through the skin, and cause blindness and nerve damage. Do not risk it, wear rubber gloves, plastic apron, and goggles whenever using chemicals. Seriously.

Lye can be had at most hardware stores, the red devil brand seems to be the preferred type by many bio-diesel makers, though in a pinch lye can be made from scratch, as well as methanol (As you now know from reading Alcohol Magic!), and anything else needed for this fuel.

Here is a recipe for Wood Ash (Potash) Lye: A cylinder like a barrel, with the bottom cut out, placed on a flat stone or tray. There needs to be a means of directing what will flow out of the bottom of the barrel, and it will of course flow from all directions out of the bottom. Place a layer of straw and small branches at the bottom of the barrel and deposit wood ash into this barrel. This operation needs to be sized correctly for expected quantitites and efficiency. It is good if wood ash fills at least 1/3 or so of the barrel/can. Slowly pour water over the ashes until a brownish liquid oozes from the bottom of the barrel. Collect this liquid. It can be dehydrated or cut with water for your individual needs. This chemical is a main ingredient in soap making too.

The main process of making biodiesel is testing the quality of your WVO. This is very necessary. This is called a Titration Process. The condition of your WVO will be effected by amount of time oil has been heated, and what was cooked in it. Fresh oil will take much less of the lye and methanol to work correctly. Hemp seed oil would work great for this I think.

The first thing most people do is obtain the oil and process it through straining. Use cheescloth, or fine mesh to remove all solids from the oil. Heating or warming helps this. Use of the other chemicals (Lye/Methanol) must be undertaken with some care. Overall you are striving for a neutral PH, around 7, but because the two other chemicals in this process will directly alter the Ph of the concoction, the titration test is necessary to evaluate your oil, and to determine just how much of the other chemicals (Again, lye/methanol) to use.

This is how you determine ratios in your process (from the Dancing Rabbit Bio-Diesel Site):

Dissolve one gram NaOH (Sodium Hydroxide -- Red Devil Lye) in 1000 ml (One Litre) of water. This is your NaOH solution.

Dissolve 1 ml of the strained waste vegetable oil in 10 ml Isopropyl Alcohol. (IPA). This is your vegetable oil solution.

With a ml eyedropper, drop the NaOH solution into the vegetable oil solution, one drop at a time. Check with Ph paper between drops. When it reaches a Ph of 8-9, record the number of drops required and calculate quantities upward.

The number of drops of NaOH needed for the vegetable oil solution to reach a Ph of 8-9 is the number of grams of NaOH (Lye) needed to raise the ph per litre of vegetable oil. To this must be added 3.5 grams per litre as a catalyst. So if it takes you six 1 ml drops of NaOH solution to raise your vegetable oil/alcohol solution to a ph of 8-9, then PER LITRE OF WASTE VEGETABLE OIL you will need 6 grams + 3.5 grams=9.5grams of Lye.

Next you must calculate the amount of methanol required to turn the WVO into bio-diesel. This usually falls between 15-20% of the WVO by mass. The best way to do this is to measure out equal amounts of the WVO and the Wood Alcohol (Methanol), weigh each, then calculate exactly what 15% by mass is. Here is an example from Mike Pellys biodiesel page (www.webconx.com/making biodiesel.htm) : If you are trans-ester-ifying 100 litres of WVO, then you will use 15-20 litres of wood alcohol. If unsure its better to go heavy on the wood alcohol, versus not enough.

The methanol is mixed with the lye (The precalculated amount) which creates what is called sodium methoxide. It will get warm during the mixing. The vapors are harmful do not breathe! It will also damage your skin pretty severely and you will not even feel it. Safety equipment is a MUST and plenty of fresh water handy for rinsing. Keep all metal that comes in contact with the lye as clean and dry as possible. This stuff also eats paint off of just about anything, so use plastic glass or stainless steel containers.

Now you mix everything together. Good agitation is a must. A paint stirrer that goes on a large drill, or propellor on a motor is necessary. It has to be a good agitation but not too much -- try not to introduce too many bubbles in it. Make it so there is a vortex just appearing at the surface in the center.

The WVO should be heated also to 120-130 degrees, although in some places on hot days a black drum can be left in the sun and will reach high enough temp to do the job.

While agitating the solution, add the lye/methanol solution over 50 mins to an hour. The reaction will generally be finished in 30 mins or so but the extended time is desirable.

After mixing and adding the lye/methanol mix, let the drum stand and cool for 8 hours at least. At the bottom of the drum is the glycerine by-product, it is dark brown. The biodiesel will float on top and is honey/yellow colored. Many remove the glycerine by means of a drain at the bottom of the barrel but skimming or dipping will work well to get the vast majority of the biodiesel out of the drum, as well as siphoning, or pouring very carefully. Do not allow any of the contaminants at the bottom of the barrel to flow out with the biodiesel. Finally, it should be possible many times to siphon the biodiesel out of the drum too. The glycerin can be composted after allowing the methanol to evaporate off for few weeks. Or it can be reclaimed and made into soaps and other useful things. Search the web for all that info.

There are several different ways to get the fuel usable from this point on, and the most simple is to let it settle for about a week or ten days. This allows any soap residues to coagulate. Once this has been done, filter the biodiesel well as it flows into the tank for use, and do not use any discolored layers at the bottom of the barrel. The end product should have a Ph of around 7 (Neutral) and it should be clear, tinted light brown.

There are many other ways of Washing and Drying biodiesel, and if you are interested visit Mike Pellys site or other biodiesel sites on the internet. Many have been shut down by big petro interests, but more crop up every day.

One of the few drawbacks of using biodiesel is that it tends to be hard starting during cold weather. This can be remedied in a number of ways, though the simplest is to mix with petroleum/fossil derived diesel fuel.