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You can make your own biodiesel. There are two versions--both are really great high energy fuels --methyl ester
biodiesel made from methanol and vegetable oil and ethyl esters biodiesel,
made from ethanol and vegetable oil. National Renewable Energy Laboratories
(NREL) found that the life-cycle energy ratio is greater than 4.0. That means you get over 4
times as much energy out of it as what it takes to make it! Plus, you can make it yourself from used French Fry oil from a
fast-food place.
Biodiesel can be used in conventional (diesel) vehicles with no engine alterations. This can take care of your fuel needs
right now, if you have a vehicle that burns diesel.
Turning vegetable oil into diesel fuel...
US Park Service truck uses Biodiesel exclusively! |
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Their biodiesel is made from Canola Oil and Ethanol. |
If you have a diesel car, you can make your own fuel from used vegetable oil from a fast food diner (or any large
restaurant). You will need either ethanol or methanol to convert the veggie oil. You will also need some lye--either
sodium hydroxide, or potassium hydroxide. Both are extremely toxic! Working with strong chemicals is scary,
nasty stuff, but you end up with a very safe and clean fuel, which is a huge difference from that nasty old diesel.
A short warning is necessary
for anyone who thinks you can use ordinary veggie oil without converting it first: I recently got a letter from someone
who spent $1,200 replacing his fuel pump and cleaning out the injectors after trying filtered veggie oil without
converting it to biodiesel first. Follow a tried and tested method, and then follow it to the letter (don't take
any shortcuts, and get a friend who knows a bit about chemistry if you need help).
You can make your own ethanol from bakery wastes, or a number of other free feedstocks, but this is can be a lot
of work, plus you need a lot of tanks, pumps, and various types of handling equipment. Distilling alcohol is
perfectly feasible to the average farmer (not usuaally so easy for someone who lives in the city). Making biodiesel,
on the other hand, can be done in your suburban garage. You can't make your own methanol,
but you can recover it and re-use it, if you take the time to learn your chemistry lessons well. I never owned a diesel,
so I find that running the still is a lot safer than messing with a bunch of chemicals. But, to each his own. Read
on....
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THE VEGGIE CAR |
Make
your own Bio-diesel
There are a number of new classes and support groups teaching
how to make your own Bio-diesel.
In Colorado, Solar Energy International in Carbondale offers a great class: just click on this photo to the left. http://www.solarenergy.org/altfuel.html
The guest
instructors are: Joshua Tickell, author of From the Fryer to the Fuel Tank, and David Max, of Montana Biodiesel.
In England, a one hour drive north of London, LILI
(Low Impact Living Initiative) offers a really great, hands-on, weekend workshop. Converting used
vegetable oil into biodiesel has a big advantage over ethanol, because there
is no need for any work to your engine, and you can
switch back and forth between diesel and bio-diesel according
to fuel availability. So if you own a diesel,
instead of building a still, you need to find a source of used vegetable oils (from
a food distribution warehouse), and then you need to learn how to work with some fairly dangerous chemicals such as sodium hydroxide
and ethanol (or you can use methanol). If you don't have
a background in chemistry, then you should take a class such as taught by Phillip Hunt. lili@lowimpact.org
The best text available, used in both classes, is, "From
the Fryer to the Fuel Tank," by Joshua Tickle. Tickell@VeggieVan.org
For more information on biodiesel, see: http://www.VeggieVan.org
Another good source is Homepower magazine. You can download the current issue, for free. Look through their archives
for recent articles on making biodiesel. http://www.homepower.org
If you want to use your home-made ethanol for making bio-diesel, it has to be 100% pure: 200 proof. But even though the Charles
803 still will make 194 proof, again and again, you can never remove that last 3% of water using a still of any kind. You
will need to use a molecular sieve. This sounds technical, but it is real easy. Just read this letter I got from Dr. Grant
Carlson with Eco-Rebuilders. "Since we remanufacture old third generation Corvettes with big horsepower-high compression-fuel
injected engines, homemade E85 is important to our customers. A molecular sieve is just zeolite: link to information about
the manufacturer we use is shown here. Buy Type 3A in 10lb bags (looks like a small pea gravel) it is only a couple of bucks
and it works very well to dehydrate the ethanol. We mix about 5lbs in a 5 gallon can and let it sit with the ethanol overnight
and pour the dehydrated ethanol through a screen, into another can the next day. To get the water out of the zeolite we just
broil it on the backyard grill - it is reusable indefinitely. http://www.thomasregister.com/olc/adcoa/molecula.htm
Ethanol Based Biodiesel
If you have a diesel engine, you can make your own ethanol and use it to change waste
vegetable oils from fast food restaurants into biodiesal. This is a good use of home made ethanol. Here is how to do it.
A BATCH PROCESS TO MAKE BIODIESAL
WITH ETHANOL
Conversion of rapeseed oil into ethyl esters for use as Biodiesel fuel involves transesterification
of the oil triglycerides to mono-esters of the component fatty acids. To accomplish this conversion, raw rapeseed oil is treated
at room temperature with ethyl alcohol in the presence of potassium hydroxide as a catalyst. During the process, the glycerol
that is produced is insoluble in the ester product, and being heavier, settles out carrying most of the dissolved KOH catalyst
with it. Upon initial settling, some of the undesirable, emulsion-forming by-products may remain in the ester layer,
causing problems in the washing stage. It was discovered (by tracking the process with a glycerol determination) that most
of these products could be removed by simply re-stirring the glycerol into the ester, adding water and letting the mixture
settle out again. After draining off the glycerol/water layer, the product (ethyl ester) can be easily water-washed to remove
residual alcohol and potassium.
INTRODUCTION
Processing
Transesterification of rapeseed oil at the
University of Idaho from 1980 to 1990 used methanol as the alcohol. Methanol is highly toxic, does not produce a visible
flame when burning, can be absorbed through the skin, and is 100% miscible with water, so any kind of spill presents a serious
problem. Ethanol provides the advantage of making a Biodiesel fuel produced entirely from renewable resources. The use
of ethanol in Biodiesel production has not been studied as extensively as has methanol.
Water washing the ester was
accomplished through sprinkling water into the tank at an approximate rate of 100 gallons per hour. As the water droplets
travel through the ester, they remove the impurities. Washing would continue for 20 to 30 hours consuming as much as 3,000
gallons of water.
Oil Seed Press
Two commercially manufactured screw type oil expellers are used for extracting
oil from the rapeseed for this project. The seed is manually fed into a 100 pound capacity tapered bin atop an auger. The
seed is heated as it moves up the auger to the screw type press. A retention time of approximately 20 minutes is required
for the seed to be heated before the oil is extracted. These two presses with augers were mounted on a movable base that were
12 feet in length, 4 feet wide, and 5 feet in height. Due to the size of these platforms and the limitations of shop space
only one press could be feasibly operated at a time.
Reactor
A 290 gallon cross-link polyethylene reaction
tank and a 50-gallon plastic Rubbermaid barrel were used prior to this grant. The reactor tank was capable of producing
200 gallons of ester per week. A sink type drain was used with gaskets in the bottom of the reactor tank to drain the glycerol
and then the wash water from the ester layer. The drain gasket was continually leaking and the cross-link polyethylene reaction
tank was warping due to material compatibility with ester and glycerol. Fluids were pumped through the use of a centrifugal
pump which required a hand primer pump to transfer the alcohol from the plastic barrel to the reactor tank.
MATERIAL
AND METHODS
Processing
Reactants
The reactants for the transesterification process are used in the
following previously determined proportions in U.S. and metric units:
Raw rapeseed oil 100 L 100 Kg 100 Gal Anhydrous
Ethanol 27.4 L 23.74 Kg 27.4 Gal Potassium Hydroxide 1.30 Kg 1.43 Kg 10.83 lb
The input amount of raw rapeseed
oil determines the batch size, and the other components are calculated from the following formulas:
EtOH = 0.2738
x RO KOH = 0.013 x RO, where; EtOH = amount of ethanol required, in litres RO = the desired amount of oil to be
processed, in liters KOH = amount of KOH required, in kg
According to these formulas ethanol is added at a 65%
stoichiometric excess, or a molar ratio of 5.0: 1 EtOH to oil. The KOH is added at 1.43% of the weight of input oil.
Quality
of Reactants
1. Rapeseed Oil (Canoloa Oil) is best when clear (filtered) because excess sediment collects on the bottom
of the reaction vessel during glycerol settling and at the liquid interface during washing. This sediment interferes with
the separation of liquid phases and with the washout of catalyst, and may tend to promote stable emulsion formation. Slight
haziness of the oil probably does no harm. The original oil must be water-free, because every molecule of water destroys a
molecule of catalyst, thus decreasing its concentration.
2. Ethanol. The nearer to absolute (200 proof), the better.
Gasoline present in the alcohol as a denaturant appears to do no harm. The reaction proceeds satisfactorily in mixtures
of 200-proof ethanol with 10%(v/v) or more gasoline present. However, even small quantities of water (less than 1%) can decrease
the extent of the conversion reaction enough to prevent the separation of glycerol from the reaction mixture.
3. Potassium
Hydroxide Catalyst. Best if it has > 85% KOH. Even the best grades of KOH have 14 to 15% water (which cannot be removed).
It should be low in carbonate, because potassium carbonate does not serve as a satisfactory catalyst, and may cause cloudiness
in the final ester.
Other catalysts which may be used are potassium ethoxide and sodium ethoxide, but they are
prohibitively expensive. Sodium hydroxide was not a suitable catalyst because it was not sufficiently soluble in ethanol and
it tends to promote undesirable gel and emulsion formation during transesterification.
The Reactions
1.
The first step is to activate the ethanol by dissolving the potassium hydroxide to form potassium ethoxide. Stir vigorously
in a covered container until the KOH is dissolved, approximately 20 minutes. Protect as much as possible from atmospheric
CO(2) and moisture, both of which reduce the activity ofthe catalyst. The entire portion of ethanol is used here. (There is
enough ethanol to accomplish the complete transesterification, with about 65% in excess.) Preparing this solution is, in effect,
preparing a solution of potassium ethoxide according to the following reaction. Reaction weights are as follows: For 100L
oil 1.3 kg x=1.07kg y=1.95kg 0.42kg
Using a 100 liter batch of oil as an example, the KOH used reacts
with 1.07kg of ethanol to produce 1.95kg of potassium ethoxide. This mixture now contains (27.4x0.789)-1.07 = 20.55kg
of free ethanol and 1.07kg of ethanol as potassium ethoxide catalyst. Any water added to the entire system reverses the above
reaction and quenches a proportional amount of the potassium ethoxide catalyst. One part of water can quench up to 84.15/18.02
= 4.67 parts of catalyst.
The ethanol-KOH mixture is then poured into the rapeseed oil, and the following
transesterification reaction occurs: (a hypothetical formula for the rapeseed oil, based on a typical oil analysis is
used):
1 Rapeseed Oil + 3 Ethanol --
3 Ethyl Ester+ 1 Glycerol
(100L or 91kg) (13.1kg)
(95.3kg) (8.70kg)
From these relationships, 100 liters (91kg) of rapeseed oil reacts with 13.1kg of
ethanol. The 21.62kg (or27.4L) of ethanol used in the batch represents 21.62/13.1x100 = 165% of that required for complete
transesterification of 100 liters of rapeseed oil. (A 65% excess over the theoretical requirement).
The Mechanics
of the Transesterification Process
1. Raw rapeseed oil is measured into the reactor.
2. The required amount
of ethanol is placed into a smaller covered container.
3. The required amount of potassium hydroxide is quickly
weighed, protecting it as much as possible from atmospheric moisture and carbon dioxide.
4. The solid potassium
hydroxide is added to all of the ethanol which is then vigorously stirred in the covered container until completely dissolved.
At this point the dissolved KOH is presumed to have been converted to potassium ethoxide catalyst. Any undissolved
pellets of KOH left in this alcohol tend to remain undissolved during the entire subsequent transesterification, essentially
decreasing the amount of catalyst taking part in the reaction.
5. The ethanol-catalyst mixture is poured into the
oil in the main reactor and stirred rapidly. Mixing is continued for 6 hours at room temperature. The reaction mixture
usually changes to a turbid orange-brown color within the first few minutes; then it changes to a clear transparent brown
color; finally, as the reaction is completed, the mixture again becomes somewhat turbid and orange-brown colored due to the
emulsified free glycerol which has been formed. 6. In a good completed
reaction, the glycerol begins to separate immediately upon cessation of stirring, and the settling mostly complete in
one hour. After initial settling, the entire contents of the reaction vessel are again mixed together and stirred vigorously
for 40 minutes. After the first 20 minutes of restirring, water is added at 15% of the initial volume of oil used in the reaction.
Stirring should continue an additional 20 minutes after the water is added for a total of 40 minutes of restoring. This
mixture is then allowed to settle overnight or over a weekend. A longer separation time facilitates the washing process. Remixing
the glycerol layer with the ester layer while adding water has the effect of collecting and removing impurities and products
of incomplete reaction from the ester. The washing phase can then proceed at a more rapid pace than if the remixing stage
were left out.
In batches where poorer quality (moisture-containing) ethanol is used the reaction will not go to completion
and requires much longer for the glycerol to separate. If separation does not occur, the addition of a small amount (perhaps
10% of the original volume) of alcoholic KOH with stirring may tip the reaction balance in favor of separation. It is also
sometimes possible with the addition of a small amount of water (0.5% of the total volume) after the reaction is supposedly
completed, to effect the separation of the glycerol from the ester. If the original ethanol contains as much as 1% water,
the reaction may be so incomplete that the glycerol may never separate, and the entire batch must be discarded.
7.
After remixing the glycerol and 15% water addition, and completion of the separation, the lower, heavier glycerol/water layer
is drained off, pumped into barrels and shipped to a recycler. A thin layer of gross glycerol and sludge may adhere to
the bottom of the reactor. It is advisable to wash down the cone of the reactor to remove this adhering glycerol or sediment
by pouring a few gallons of cold water down and around the inside circumference of the reactor. This should be done at least
twice. Any sediment probably consists of a host of minor components of the original rapeseed oil (proteins, glycoproteins,
waxes, sterols, carotenoids, phosphatides, carbohydrates, etc.). Some of these constituents are emulsifying agents, and others
have affinity for water which causes hold-up of undesirable impurities(e.g., potassium) and tend to prolong the washing process.
8. Finally, in order to remove the remaining alcohol and trace amounts of potassium, glycerol or soap, the ester is
washed with water at about 30% of the ester volume or 30 gallons of water to a 100 gallon batch of ester. The water is stirred
into the ester with mechanical stirring and air agitation as described in the next section. After a few hours the stirring/aeration
is stopped and the water is allowed to settle out for two to three days. At this point the process is complete and the crystal
clear product can be pumped into fuel tanks for storage or immediate use.
The Washing Process
Washing the
ester product is necessary in order to improve its fuel properties, largely by removing residual free glycerol and small
amounts of potassium remaining from the catalyst. The best method so far devised was previously described. It is a combination
of: 1. Mixing the glycerol layer into the ester after the initial settling has occurred; adding 15% water; stirring and settling.
2. A water wash with agitation and aeration after the glycerol/water layer has been drained off.
Soap Formation
Soaps,
at least in trace amounts, can be formed by an accompanying reaction during or subsequent to the transesterification process:
O O RC-OC(2)H(5) + H(2)O-------- RC-OH + C(2)H(5)OH
Ethyl Ester Water Fatty Acid Ethanol
This is an
equilibrium reaction, and any base will neutralize the acid formed, removing it, and forcing the reaction to the right.
Also the reaction product of the base and acid is an undesired substance (a soap, which is an emulsifying agent).
O
O RC-OH + KOH-------- RC-OK + H(2)O Fatty Acid A Base Salt/Soap Water
These reactions have little tendency to
occur during the transesterification because of the small amount of water in the system. The source of the interfering
water for this reaction may be use of low-grade water-containing ethanol, water in the other reactants at the beginning from
atmospheric exposure), or even from the first stage of the water wash. In any case, only a trace of soap needs be formed
to promote emulsification of the ester with the wash water.
Wash Methodology 1. Agitation. During washing, many
of the impurities in the ester have a greater affinity for the water, and they are transferred by diffusion across the
phase boundary into the water. This process is greatly hastened by agitation, which can increase the area of phase contact
by emulsion formation, or can promote transfer by maintaining the most effective concentration gradient for transfer across
the interface.
2. Mechanical Stirring. Best results have been obtained using a mechanical stirrer whose rotation
can be strictly controlled. The best speed for the equipment used has been about 50 to 70 RPM. The stirrer shaft should have
two blades with one in the water phase and one in the ester phase rotating to lift the solution upward. This orientation,
along with aeration develops maximum contact between ester and water.
3. Aeration Mixing. A unique method of aeration
mixing was discovered. If air is introduced deep into the water layer through a sandstone, glass or stainless steel
gas diffusion disk numerous air bubbles are formed in the water phase. These numerous water coated bubbles rise through the
liquid interface into the ester, carrying large amounts of water in the film, and accomplishing washing as they rise up through
the ester. Upon reaching the surface, the bubbles burst and form droplets of water which fall back down through the ester,
further washing it. These bubbles and droplets seem to be of such size and nature that the droplets formed do not remain emulsified
when they reach the aqueous phase, but quickly coalesce and disappear into the aqueous layer. This method greatly magnifies
the interface area, and at the proper aeration rate, half or more of the ester phase volume seems to be filled with quite
rapidly settling droplets of aqueous phase.
4. Combination Aeration and Mechanical Stirring. By combining (2) and
(3) above very efficient and rapid washing can be achieved using minimum amounts of water.
Product Completeness
1.
Bench Wash Test. Throughout the washing, a rough idea of the completeness of the washing may be obtained by washing (in
a 100 ml beaker with magnetic stirring) 50 ml ester with 25 ml water for about 1/2 hour, and then determining the pH of the
wash water. If the ester is sufficiently washed, the pH should be around pH 6 to 7. There is also a good way to determine
washing completeness by noting the emulsion-forming tendency during this beaker wash-test. If the wash has been satisfactory,
it is possible to stir a sample rather vigorously in this test and form an emulsion of large, clear, shiny droplets which
will quickly separate, settle, and disappear upon cessation of stirring.
2. Turbidity. Occasionally a batch of washed
ester may end up with turbidity caused by traces of condensed moisture. This moisture may be conveniently removed (evaporated)
by aeration with dry air, using the gas diffusion disks from the washing step, to increase the surface contact between the
air and the ester. Slight warming along with the aeration also hastens the removal of this trace of moisture.
Process
Optimisation In the development of the above procedure for producing high quality ethyl esters, A.O.C.S. method Ca 14-56
for determining total, free and combined glycerol was used to follow the process. Procedural methodology was determined
on the basis of percent glycerol left in the product after each step. Due to health and safety concerns, heptane was used
as the solvent in place of the recommended chloroform. It was found to be very satisfactory. (n-Hexane and 2,2,4Trimethylpentane
were not satisfactory)
Five sets of tests were made, each with 6 small beaker batches of REE. Batches were made
according to the recipe previously described and allowed to settle for 30 minutes (except for the first one) before further
treatment took place. Methods and inputs were generally kept constant except for the one being studied. Glycerol determinations
were made on samples settled for at least 24 hours after treatment.
Viscosity vs. Total Glycerol At first, a direct
correlation between viscosity and glycerol was determined using A.O.C.S. Ca 14-15 (Figure 1). It was an effort to test the
method for accuracy and reliability by spiking some relatively pure REE with various amounts of pure glycerol. The cluster
of points at the lower end of the graph represent production grade product. It was found that this correlation only holds
true for washed esters. REE at intermediate stages may contain some alcohol which affects the viscosity reading. Addition of Water
1. Amount of Water. In this set all samples were allowed
to settle then remixed with glycerol for one minute before water was added with the exception of the first one in which
water was added at the end of the 2 hour reaction time. All samples were stirred for 3 minutes after water was added. At
this stage of the process it was found that increasing water could be tolerated to the point where a permanent emulsion was
created, which was approximately 30% by volume of the original amount of input oil. Water has very little effect on combined
glycerol but that it significantly reduces free glycerol in the ester. The amount of water added to the mixture that effected
the highest glycerol removal was found to be 20%. This figure will vary according to the quality of the raw products used
in the reaction. Poorer quality reagents will produce a product higher in mono, di, and triglycerides and thus will tolerate
less water before a permanent emulsion is formed. This was the reason that 15% water was recommended. Notice also in Figure
3 that a point in the upper left hand comer shows the effect of adding water at the end of the reaction without first letting
the glycerol settle out. It was higher in glycerol, which suggests that the action of settling and remixing before adding
water decreases combined glycerol. It can be said that some amount of mono, di and/or triglycerides are removed or converted
by the glycerol only remix. 2. % Glycerol vs. water added after
one minute of remixing the glycerol into the ester layer and mixing the water for three minutes.
3. % Glycerol in Biodiesel with one minute remix of glycerol into the ester and
20% water added to the reaction versus mixing time.
2. Time of Water Remix. In this set the small beaker batches
were remixed with glycerol for one minute before the addition of water except for the first one which was stirred for
10 minutes before water was added. Water was added at 20% of the total for each sample. Stirring time varied from 1 to 30
minutes. In Figure 3 it can be seen that the glycerol decreased steadily with time. Twenty minutes was chosen as the cutoff
time for the remixing. Data from the first point (10 min premix) confirmed the idea that combined glycerol can be reduced
and prompted the next set of tests in which the glycerol only remix was lengthened.
Glycerol Remix
In this
set of tests the glycerol only remixing time was varied from 5 to 30 minutes. All samples then had 20% water added and
continued mixing for 10 min (first four) or 20 minutes (last two). Figure 4 shows that the combined glycerol does in fact
decrease, confirming again that some amount of mono, di and/or triglycerides are removed or converted in this process. The
free or dissolved glycerol actually increased with time, however the final water wash should effectively remove all but a
trace of it. The lowest glycerol readings were from the sample which was re-stirred for a total of 40 minutes, 20 minutes
in glycerol only mode and 20 minutes after the 20% water was added. These were the parameters chosen as a pre-treatment to
the final water wash and can be referred to the 20/20/20 rule for treating batch processed Biodiesel. As was stated earlier,
the amount of water added should be reduced to 15% if the reagents are not of the highest quality.
4. Varying
glycerol remix into ester times with 20% water added after the remix and then mixed an additional 10 minutes. The shorter
graph lines are with 20 and 30 minute glycerol remix times with 20% water added and mixed an additional 20 minutes.
Oil Seed Press
A seed press stand was designed and built for the seed to be
above the press and gravity fed. This eliminated the need for an auger and reduced the size of the base to seven feet
long, five feet wide, and a height of 11 feet. The seed bin was sized for a 2,000 pound capacity of seed and placed on a digital
readout scale. The meal bin was positioned beneath the seed bin and was also placed on a digital readout scale for monitoring
the press efficiency. A seed heating chamber was sized for the seed to have a retention time of twenty minutes before entering
the screw-type press. The second press was positioned so the gravity feed seed tube was connected to the bottom of the existing
funnel-type seed bin. This allowed for simultaneous press operation and a minimal amount of monitoring the presses and seed
bins (due to the seed bin capacity of two days).
Reactor
A 400 gallon capacity 316 stainless steel, 10 gage
cone bottom, open top tank was mounted on a 6 foot by 8 foot portable platform. An 80 gallon poly tank with a cone bottom
for the alcohol and catalyst mixing was mounted next to the stainless steel reaction tank. The centrifugal pump was mounted
below the plastic alcohol tank eliminating the need for a hand primer pump. An air driven transfer pump is used to transfer
alcohol form barrels to the poly alcohol/catalyst tank. A hydraulic motor with a shaft and mixing blades was mounted to the
top center of the reaction tank for the washing process. Aeration tubes for the washing process are introduced to the
reaction tank during the washing process.
CONCLUSIONS
Developments in processing rapeseed ethyl ester
have been dramatically improved during the course of the past two years. Remixing of the glycerol layer with the ester
layer for 20 minutes and then adding 20% water and continuing mixing for an additional 20 minutes has reduced the amount of
water used from as much as 3,000 gallons to 150 gallons for a 200 gallon batch of ester. The remixing of glycerol and water
also reduced the possibility of forming an emulsion during the water washing process.
The gravity feed system
for the oil seed presses has allowed for two presses to operate simultaneously with minimal amount of labor. The seed
bin requires filling once a day and the meal bins are emptied every other day.
A larger reactor tank and alcohol/catalyst
mixing tank mounted on the same platform has increased production by 1.3 times that of the previous reaction tank. Pumping
procedures have been simplified along with handling of the alcohol. http://rredc.nrel.gov/biomass/doe/rbep/biodeg/one.html |
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Will your still help me make biodiesal? Can it make
methanol?
Methanol cannot be made with a still. It is a by-product of the Natural Gas industry. You can make
biodiesal with ethanol instead of methanol, though.
I give a recipe for this lower down on this page. --RW
Robert, Thanks for the reply. I could use ethanol for the production of the biodiesel, but it
is significantly cheaper to use methanol since since you get many more moles per unit volume of methanol than ethanol, which
translates to cheaper biodiesel. I am using a starting material where I must first do an acid-catalyzed step (with
excess methanol driving the reaction to completion), and in this step, water is a byproduct of the reaction. I
want to use the still to separate the excess methanol used in the reaction from the water produced during the acid reaction,
and from the biodiesel/glycerin itself at the end of the reaction. So I am only going to use the still for
the purification of the methanol for re-use, not for the production of methanol. I believe your still would be
a inexpensive way to do this with maybe the modification of the operating temperature.
Regards, Eric
Eric, Are you following the dual-stage methanol production process?
This is what it sounds like. Then you may have a bit of oil to remove, but that should come out OK in the bottoms water. Or,
better yet, remove it first by letting it set for a day or two, so you can pour it off the top.
Methanol's boiling point (=condensation point) is 64C. Pure ethanol alcohol boils
at 174 F (78.9 C). Conversely, alcohol vapours condense into a liquid at 174F (78.9 C). You just adjust the temp control
with a screwdriver, and watch the temp gauge while you do this. You can get it to be accurate within 1/2 of 1 degree
F., so this will give you back really pure methanol.
The great thing about my still is, that with the automatic temperature
control valve, you can set the still to distil methanol and then you can re-use it. Most people I know just let it evaporate,
but then, they don't make enough to make it worthwhile to recover it.
Be very careful, though, to work in an open ventilated shop, as methanol
fumes are really poisonous, whereas ethanol is much safer.
Good luck, Robert Warren
How to make Biodisel using Ethanol and French-fry oil.... Click this link for a 26 page report.
Butanol is another amazing
alternative fuel, because it can be made from things like rice straw and old newspapers. It has
as much energy as gasoline (BTU'S/gal), it burns with the same air/fuel ratio, and it will even mix with gasoline which
means that you don't have to drain your tank first in order to use it. You don't even have to re-tune or adjust your engine. The
best part is that it can even be made from lawn clippings and leaves.
Butanol
is normally made by anaerobic bacteria feeding on cellulose, and it is damned smelly stuff, stinking beyond belief. It
reminds me of toe-jam! But it is also a well-known chemical by-product, and is used for tons of things, especially the perfume
industry, but usually in tiny quantities. It is related to Butyric acid, which is what synthetic orange and strawberry flavours
are made of. It is hard to believe you make one out of the other, with such a God-awful smell, but then,chemistry is an amazing
science.
While I have read various pieces of literature on the
subject, I only have personal knowledge of two people who ever tried to make it. The first was Pete Charles, the same person
who designed the Charles 803 alcohol still which I have written about extensively. (I have built this still over 130
times.) Pete tried to make it from lawn clippings (ordinary grass). It is a biological decomposition, via an anaerobic
process (no oxygen), but the smell was so bad, and extremely difficult to get rid of the smell afterwards. In fact it was
a serious nuisance! Several other by-products, including butyric acid, are produced (although in small amounts), but
they are can be a serious danger to eyes, nose, and skin. The biological bacteria process is an organic process,
but yet it has to be very closely controlled in a sealed environment, preferably sealed stainless steel or very heavy
plastic fermentation tanks, with closed pumps circulation for mixing, and large sealed plastic settling tanks. I really don't
know enough about this process to help you make it. But that's what the Net is for, right?
The other person I met during this period, about 20
years ago, was Dr. Sydney Levi, a former chemistry professor, chemistry textbook author, and holder of many patents involving
plastics extrusion processes. He was going to build a huge $3 million dollar plant in Fresno, Calif. and convert rice straw
to butanol. He said he had the funding in place and he was working on his proposal full time when I met him. He had made it
in his laboratory many, many times. I spent over an hour with him, he showed me the plant diagrams and chemical
processes for how the process would work. We discussed many different issues, as I was at that time writing freelance articles
for a trade journal, Gasohol, USA. Somehow, the project died, and I moved to Oregon, and I never was able to follow up
and find out what happened.
More recently, a US government group in Colorado,
NREL Laboratories, has done some research on this subject and has some articles available on the net. I visited their facility 4
or 5 years ago and got a private tour, where they showed me the complex laboratory where they were researching acid hydrolysis
in combination with biological decomposition of various lignums and cellulosic materials. They said it looked completely
feasible in terms of economics. But doing something successfully in the lab and then making it work in the real world are
two different things entirely. You need a lot of money and a lot of scientific knowledge.
Butanol data sheet
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The acetone-butanol fermentation has a long history as a successful industrial fermentation process. The earliest was work performed by
Pasteur in 1862. Butanol is a commodity chemical feedstock and solvent that was primarily produced by industrial fermentation.
In the early 1900s, butanol was used to produce butadiene which was the most desirable raw material for synthetic rubber.
The annual production of fermentation derived butanol was over 45 million pounds during 1945. But the fermentation-derived
butanol process declined after World War II in the U.S. due both to changes in availability of renewable feedstocks (molasses,
sugar cane) and the increase in availability of inexpensive petrochemical feedstocks. Butanol fermentation of beet molasses
continued through the 1970s in the Soviet Union and fermentation of sugar cane molasses through the 1980s in South Africa.
Butanol is now synthesized chemically from petroleum derived ethylene, propylene and
triethylaluminum or carbon monoxide and hydrogen. The major domestic producers of butanol and its derivatives are BASF, Chem
Service Inc., Dow Chemical, Eastman Chemical, Hoechst Celanese, Shell, Union Carbide and Vista (Chem Marketing Report, 1991;
Chemical Economic Handbook, 1990). The current U.S. production of butanol is more than 1.2 billion pounds per year and is
experiencing a growth of 3-4% annually.
"This is a presentation I gave to the Colorado Department of Agriculture Seed Growers' conference
in 1994. Not that much has changed in terms of farm commodity pricing." -- Robert Warren
Vegetable oil to replace diesel?
By Robert E. Warren May, 1994
Since today is devoted mainly to vegetable oil production, I will speak mainly about the prospect of using vegetable oil
as a fuel.
American farmers are an economically oppressed class of people. They are also the hardest working and most self-reliant
and inventive people around! Farmers have to buy retail and sell wholesale, as well as borrow money year after year just to
plant a crop which may cost more to grow than it will sell for. In fact, most of our commodity crops are still priced very
closely to what they were bringing in the early 1950s. Wheat, corn, potatoes, milk, and even eggs and honey are good examples
of this.
We met farmers in our work during the early 1970's who were making their own fuel for their trucks and tractors,
instead of paying the doubled price of petroleum. There was a real movement in this country to be self-reliant, and making
your own fuel (as well as giving birth to a wholly new domestic industry) was starting to take hold.
When it looked
like we are gaining too much ground in getting a new alternative fuel industry started, the oil giants use their economic
power to fight you by lowering gas prices back down. So, in 1983, oil prices were reduced back down to a level where people
were again comfortable with buying their gas, at maybe $1.25 per gallon, and alcohol and veggie oils were no longer a competitor,
since alternative fuels needs to be priced above $1.45 /gal to be profitable for its producers.
Research
on vegetable oils virtually stopped, after the gasoline prices dropped, even though over 100 scientific papers on vegetable
oil as fuel were submitted to the US Department of Agriculture the previous year.
However, interest has continued overseas,
such as work by Volkswagen of Brazil, which has run extensive testing of soybean oil on light diesel trucks. They found very
little wear problems associated with soy biodiesel after 100,000 miles. Torque, power, and fuel consumption was very similar
to diesel, with less smoke, carbon monoxide, and pollution.
The Institute of Agricultural Engineering in Austria has
run tests on 33 tractors by 12 different manufacturers, running on rapeseed oil (now commonly called Canola oil), with good
performance, and lower emissions. Other tests run in Sweden, France, Italy, and Spain show that soybean, rapeseed, and sunflower
oil can give similar power, torque, mileage, and general performance in diesel trucks and other vehicle with no modification
whatsoever. Of course, you have a different economic climate in Europe, where diesel sells for $5 per gallon due to market
influences and heavy taxation.
This is a big difference between alcohol and biodiesel fuel. To use alcohol in
place of gasoline, some carburetor or fuel injector modification is necessary, as well as a fuel pre-heater, and changes in
timing and preferably, the compression ratio, if possible. High-proof alcohol still contains a small percentage of water (10%
H20 in 180-proof), and this will cause problems if mixed with gasoline. Also, there may be some corrosion in the fuel tank
or in the carburetor from grain alcohol. But, by adding pure alcohol to vegetable oil, to create biodiesel, no engine conversion
or tinkering is needed. Most any diesel engine can run on vegetable oil which has been convertered into biodiesal.
By
mixing anhydrous grain alcohol with vegetable oil, about 20%, a chemical reaction, producing ethyl esters, occurs which prevents
vegetable gums from forming in the oil, so you don't get the injector clogging that you get with straight vegetable oil. This
is what biodiesel is. Then, you have a clean, renewable fuel that is domestically produced, and does not require an expensive
military presence in the Middle East. This process also involves working with dangerous chemicals like sodium hydroxide, so
a fair understanding and experience of chemistry is necessary. The upside is, if you start making biodiesel as a
business, you you a ready-made market: there are millions of disel engines.
In 1991, the price of soybean
meal was $256/ton, which, made into soy oil, would yield biodiesel at a price of $1.26/gal. Now, if you look at the average
price of diesel fuel, at a farm delivered price or $.85/gallon, and compare it with the price of soy meal over a 10-year period,
with an average 44% oil content, the price of biodiesel from 1981 to 1991 could have cost less than #2 diesel for 8 out of
10 years. In addition to the fuel, you will also have a left-over feedstock with a 10% residual oil content, worth about $30
to $35/ton.
Studies by the University of Idaho of rapeseed oil and safflower oil for fuel showed that safflower oil
could be produced at about $1.35, and that exhaust emissions could be reduced by about 65%. It has been suggested that with
some minor economic or tax incentives, biodiesel would quickly become a very attractive fuel, one which could compete with
#2 diesel on the open market, and at the same time making a significant contribution to reducing pollution.
Although
in the USA, soybeans would be the logical candidate for making biodiesel, each country and each climate can and should explore
their own agricultural resources for fuel production. In some areas peanuts, or corn, safflower thistle, or sunflowers will
be the predominant fuel crop.
Here in Colorado, you seed growers already know what you can grow, and if you as a group
formed a farmer-owned biodiesel fuel co-op which centralized your fuel production in one modern, efficient facility, then
it wouldn't be long before other such co-ops sprang up in other parts of the country.
First of all, you wouldn't have
to compete with #2 diesel on the open market, as you all have your own requirements for diesel fuel. Secondly, you will still
have a high-protein feed by-product which, with the oil removed, won't go rancid, so it can command a premium price in the
feed industry. So you get your commodity price and fuel, as well.
In just three or four years, we are again going to
see some kind of minor crisis which provokes another dramatic price increase in petroleum, and you could by then be enjoying
complete energy and financial independence.
I really believe that the farmers of this generation have the tools, the
materials, and the technology to take on the big oil companies. We just need to spread the word that this is a do-able technology,
that it makes sense, and that we can make a change which makes a difference. This is a business which can create profits and
at the same time reduce pollution.
Plus, if we recycle the organic waste products back into the soil like our fathers'
generation has always done, we also create a sustainable future for our children.
© 1994, 1999 Robert E. Warren
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Robert Warren's Still
Willie Nelson: On the Road Again with Biodiesel
Maui, Hawaii - July 19, 2004
Willie Nelson has fueled millions of fans worldwide with music for decades, but when it comes to his fuel of choice, the
country music star has proclaimed himself a fan of biodiesel.
Biodiesel, an alternative fuel made from renewable fats or vegetable oils, can be used in any diesel engine, including the
star's 2005 Mercedes 320 CDI. Nelson picked up his brand new vehicle at the dock and drove it straight to the pump at Pacific
Biodiesel, a Hawaii-based manufacturer.
"I am absolutely a fan of biodiesel," Nelson said. "I use it in my car because I'm a firm believer in using renewable fuels
that are better for our environment. We should all be doing our part to reduce our reliance on foreign oil and contribute
to our own economy. On top of all that, biodiesel use helps our nation's family farmers, while preserving the land for future
generations."
"Many people like me who grew up in rural America were raised on Willie Nelson's music and revere him as a musical giant,"
said Joe Jobe, executive director of the nonprofit National Biodiesel Board (NBB). "He is adored by millions around the world,
and his support for biodiesel will be a tremendous help in raising awareness for the fuel."
"When I fill up at Pacific Biodiesel, I'm doing something good for America, and that makes me feel better about my personal
impact on the planet."
- County and Western Singer Willie Nelson
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