This is not for those who don't like failed batches; the proportions and process methods are still under experimentation.

THE PROCESS IS AIMED AT HIGH FFA CONTENT OILS AND ANIMAL FATS WHERE UNDER NORMAL BASE REACTION LOW YIELDS ARE ACHIEVED (<65%).

CAUTIONS
Keep your chemicals clean and dry
Use separate vessels for blending the acid and base with methanol
Remember methanol vapours are highly flammable.
Add acid SLOWLY to methanol
Wear safety equipment, cover all skin, use a face shield, respirator and rubber gloves.
Wash all equipment properly after use to remove residues.
YOU ARE RESPONSIBLE FOR YOUR SELF AND OTHERS AROUND YOU!

(Every one should know all that so lets continue)

Our trials of a single acid reaction did not produce any useful quantities of ester.

The FATTA method - Development by Kevin Tidball and Michael Fox

First stage acid catalyst (to esterify the FFA)
Oil 1000ml
CH3OH 100ml
H2SO4 (conc. 98% 18M) 1-2ml
React at 48- 54C until titration falls to a minimum hopefully 2.6 ml could take longer than 2 hours. Greater levels of acid will raise the titration end point.

Second stage alkali catalyst (transesterification of the oil)
100ml methanol
6.4grams of NaOH
(3.5grams for catalyst + 2.9 grams for acid neutralisation if titration of 2.6ml achieved)
React at 48- 54C for 1 hour.
Settle and separate.

If a gel forms in vessel on cooling reheat to >60C and cool slowly.
Filtering could be required to separate glycerol and soaps from ester.

What happens to the H2SO4, it is neutralised
2NaOH + H2SO4 ---> Na2SO4 + 2 H2O

This produces water, but no more than when neutralising the FFA with a base.

An example of the acid reaction.
2000ml Fat at 50C
400ml CH3OH (Higher volumes of Methanol were used in the original experiments)
2ml H2SO4

Reaction time (minutes) titration value (ml)
0 4.0
30 3.4
60 3.2
90 2.8
120 2.6
Indicated a reaction time of 2 hours was needed.

The following is a comparison of the same oil with a high FFA content (cottonseed) several trials were performed and the results were within 50ml for each. The change to KOH as the catalyst allowed better measurement of the by-products.

CONTROL
Base Catalyst Transesterfication (BCT)
Initial Titration 7.6ml
2000 ml Oil, @ 55 C
375 ml Methanol,
31gm KOH added
Temp between 48/54 C stirred for 1 hour
Yields - Methyl ester and soap 1300ml - 65%
Glycerine 900ml
Colour - 2 layers obvious difference between ester and glycerine layers.
Ester is a dark chocolate colour

Experiment - H2SO4 / KOH 2 Stage reaction.
Stage 1, Acid reaction to reduce FFA
Initial Titration 7.5ml
2000 ml Oil, @ 55 C
300 ml methanol,
2 ml H2SO4
Held fat temp between 48/54 C stirred for 2 hours.
Titration at end 3.3ml
Boil off water produced by acid reaction

Stage 2, Base Catalyst Transesterfication
Mixture was let stand for 1 day,
Titration had risen to 5.5ml
375 ml Methanol,
26gm KOH added
Held Stage 1 product temp between 48/54 C stirred for 1 hour
Yields - Methyl ester and soap 1850ml - 92.5%
Glycerine 425ml
Colour - Little difference in the colour of ester and glycerine layers.
Ester is a dark colour. Separated by density.


Conclusions
1. Good yield improvement can be achieved.
2. Viable if titration value of oil/fat is greater than 6ml.
3. During the trials differing quantities of methanol were used, 300ml was settled on as it appeared to last 2 hours.
4. Better results could be achieved using a retort vessel to maintain the methanol level in the reactor. This could also assist BCT reaction

Notes:
1. Oil volume at 55C 2000ml at room temperature this reduces to 1900ml.
2. Most of the methanol is boiled off during the acid reaction as the volume at the end of the reaction the volume was only slightly greater than the original 2000ml, this could be water created by the acid reaction.
3. Colour of Methyl Ester after acid stage is considerably darker than the Control BCT reaction.

This information is provided for people who like to experiment, and I would like to hear from any one working in this area.

The reaction is still primarily a BCT, as I have had no success with straight Acid Esterification

Kevin

The trial batches were all loaded into the bubble wash tub.

Soap removal was low, but no real figures were obtained.

Fuelled up the Ute with approx. 30 lt.

No initial side effects, smells the same, just like a fish and chip shop.

Can the aromatics be reduced or altered?

Kevin

My VW TDIs have simple oxygenation catalysts on the exhaust. With low sulphur mineral fuel I get a faint smell sort of like gas boiler flue. With Biodiesel there is no smell at all - presume because there's zero sulphur in biodiesel.

Hi Kevin,

I like your experiments.... thanks. On your Acid/ Base 2 Stage update, did you really end up using 33 percent Methanol for your completed project? If so, are you recovering any?

Dave,

Does the oxygenation catalysts also effect the NOx output?

I expect this will be our next major hurdle, as various clean air ACTs come into force through out the world.

I read somewhere that it is expected that the allowable NOx output will drop to 2.5 ppm in the next couple of years.

Roger,

Yes methanol usage is high at present, but the main aim of the experiments to date has been to increase yield specifically from animal fats.

Most of the methanol boiled off during the Acid phase, I expect that this will be recovered with a closed system.

VP’s results indicate that methanol usage can be reduced to 11.5% for a BCT process, I’ll be happy with under 15% methanol and yield greater than 85% from high FFA animal fats (greater than 6ml titration). I’m NOT asking for much!

If you have been following the discussions in VP’s touchless system. I’ve asked VP quite a few questions. Next project is to build a 300 lt sealed vessel with vacuum.

[This message was edited by Kevin, Melb. on 01 February 2001 at 11:12 PM.]

I recently noticed that Aleks Kac placed a new recipe on the Journey to Forever site that addresses our topic really well. He seems like a pretty sharp guy! It would be interesting to compare yield results.

New - High Yield with High FFA oil Recipe

The recipe seems very similar, and from a guy who originally canned the idea when I first raised it on the Egroup/Biofuel-biodiesel forum. Check out the threads 1514 7-Dec-00 onwards.

I’m not upset about the recipe, BUT patent pending? There's a challenge.
Compare the recipe above and let me know the difference.

This is the reason the above recipe was posted. Patents are only valid if they have not been presented publicly before the patent application is lodged.

Kevin

If you are worried about patents and believe that you made public the basis for the other persons recipe before they made their recipe public then you should contact him and find out just what patent is pending. If it is a US patent then you should in turn go to the US Patent Office web site and find out how to let them, tghe patent office, know about "prior art", your previous posting of the recipe.

In the software industry, which I work in and where software patents are a huge problem, the US Patent Office is renowned for granting patents when there is blatant prior art on an application- hence no patent. Basically they don't know what is going on and appear to be granting patentss knowing that people will fight it out in the courts in the long run thus sorting things out.

Andrew

Important NOTE:

For the highest yield,

Water MUST be removed before processing AND between the Acid and Base stages.

What happens in the Acid catalyst stage,

Free Fatty Acid (FFA) + Methanol <--> Methyl ester + Water.

Only small amounts of ester and water are formed, but the water component becomes significant as the FFA level increases.

There will be significant quantities of water generated with high FFA that will reduce your overall yield.

Water in the Base Catalyst reaction whether single stage or 2 stage (with or without FFA) creates SOAP!

At the same oil titration level (say 5ml) we have seen 10-15% variation in yield from dried WVO to wet WVO.

If you don’t titrate you DON’T know how much water you are creating.

Comment to those attempting the FOOLPROOF Method – (Rev 1).

“BOIL OFF THE WATER BETWEEN THE ACID AND BASE STAGES”
as per our operation above.

Kevin

Here is the experiment that I have a question for:

"
Stage 2, Base Catalyst Transesterfication
Mixture was let stand for 1 day,
Titration had risen to 5.5ml
375 ml Methanol,
26gm KOH added
Held Stage 1 product temp between 48/54 C stirred for 1 hour
Yields - Methyl ester and soap 1850ml - 92.5%
Glycerine 425ml
Colour - Little difference in the colour of ester and glycerine layers.
Ester is a dark colour. Separated by density.
"

Is the 26 gram figure too high? or was it required for the reaction?

Did the previous acid stage remove all the FFA

What is the starting percentage of FFA in the cottonseed oil

Is the cotton seed oil here a used oil or is it new oil.

comments:
mentioned is the methyl ester/soap as being the top layer. There should be more soap in the lower layer as soap is more soluble in crude glycerol/glycerol than it is in methyl ester.

In the US (and I think ONLY the US) a patent can be granted despite previous publication, the grant of a worldwide patent can also be granted on the basis of a US one.

Prior art blows this out of the water of course.

The acid catalyst method is nothing new. Prior art blows this out of the water, yes. And people have been working on these reactions at univeristies, like the U of Idaho, for a decade or more. I wouldn't worry about the patent. Just keep grinding it out as we all want to see how good you can get it to work.

PTFE

I’ve been off line for a while, and not doing much more research, but I’ll try to answer some of your questions.

The 26gm of KOH is based on standard titration
(titration + conversion) x KOH molar mult x litres
(5.5 + 3.5) x 1.4 x 2 = 25.2 (we round up to the next gram)
I have not tried to reduce the KOH level.

These comments are the posturing of an engineer from bits of information gleamed from various persons both net and face to face.
So the chemists out there, fell free to correct any misinformation.

What we expect is happening (but cant really tell unless a gas chromograph is used). The acid appears to work on the FFA first, and with time the titration will fall to a value equivalent to the acid level in solution.

The acid reaction with FFA creates esters and water toward a stable point. When equilibrium is reached most for the FFA has been consumed, but when let stand over night changes in temperature etc could be forcing the reverse. Things to note most of the methanol had evaporated which could be assisting the reversal.

The starting titration was 7.6, for the experiment. (The conversion to FFA slips the mind at present, a chemist’s task).

The cotton seed oil is used and can have a titration value as high as 14, the harder it is used by the shop owners the higher the titration.

The ester/soap is the pre washed material, with settling time or washing small quantities of soap can be removed.

Experiments yet to be tried.
1. If the stage 1 is reheated – does the titration drop
2. If methanol level is maintained - does the reaction appear to reverse
3. Closed system operation with reduced methanol

I've had a go with 98% H2SO4. I really must have a closed reaction system. But then I also think base/base is better in a closed system. If temperature is kept below 60C there should be no need for a vent condenser. A safety relief valve is a must.

The oil was horribly dirty with a large solid fat content but perhaps not too much FFA. The acid reaction went well with methanol fully mixed before adding acid. It was reacted for 90 mins then stopped with 1.5g per litre NaOH in the minimal amount of methanol to dissolve. After 12 hours, I drained off about 3 to 5 litres of thick pale brown byproduct. I think this is important as it removes water and free glycerol that would otherwise affect subsequent reactions.

A week later (I work away from home) there was a 10mm layer of saturated fat scum on the surface. I checked the drain, but only stuff the colour of the top ester came out.

I reacted again this time with methoxide at 1.5g per litre NaOH in 10% methanol. After 8 hours settling it had not completed so I drained off some byproduct. This time very dark brown/black and runny.

I did a second base reaction with 1g per litre NaOH in minmal methanol (already more than enough in there). After settling pulled off some more black stuff.

In total I got about 15 litres of byproduct from a 160 litre batch. If all the FFA is reacted, this is about right and should be almost 100% glycerol and glycerol soap. Acid reacted ester is darker. I hope it can't be mistaken for left over red diesel dye

The ester washed fine with no permanent soaping so the FFA/glycerol must have been reacted/removed. A guessed dose of citric acid in first wash sorted the ph. It's now ph7 and on it's third water charge.

I use 50 litres of water per 150 of ester and change it 3 times. The third wash bubbles for 3 days then the ester is allowed to sit on the water for another few days. I use it when I can see the water layer with no visible clouding.

My wash tank has an upward facing outlet pipe just above the water level, so I can pull off the dry clean ester.

The wash system works well. My last 2 stage alkali batch was tanked up into jerry cans. I put them into the car last night and there was no sediment.

As the acid/base process uses so much excess methanol, I think the ester should be distilled.
There is so little byproduct removed and the wash water is full of methanol - very smelly.

PS no exhaust catalysts currently available for cars can stop NOx. But if you want to run on 100% get the injection timing retarded 2 degs and NOx will be the same as on Dino. The snag is it'll be sluggish when back on dino.

>Aleks Recipe !
>The recipe seems very similar, and from a guy who originally canned the idea when I first raised it on the Egroup/Biofuel-biodiesel forum. Check out the threads 1514 7-Dec-00 onwards.
>
>I’m not upset about the recipe, BUT patent> pending? There's a challenge.
>Compare the recipe above and let me know the difference.
>
>This is the reason the above recipe was posted. Patents are only valid if they have not been presented publicly before the patent application is lodged.
>
>Kevin
>
>posted 05 February 2001  06:17 PM

I'm surprised to see this here, with no further comment from Kevin. At the time he posted a similar (indignant) message to the Biofuels mailing list. He duly received a response and expressed satisfaction at the outcome. He should have said so here, IMHO. Since he didn'y, I'll cross-post the whole exchange here for the reord - please see Kevin's final response at the end.

Keith Addison

Journey to Forever

To: biofuel@yahoogroups.com
From: Keith Addison
Date: Tue, 6 Feb 2001 21:04:40 +0900
Subject: [biofuel] Re: The FOOLPROOF way to make biodiesel

kevteeau@yahoo.com.au wrote:

>Well as for first!
>
>Check out,
>http://www.mauibiodiesel.org/discussionforums.htm
>
>Under the acid estification section.
>The Alek's recipe propotions look very similar the ones posted at the
>mauidiesel site.

Hi Kevin

Indeed, they're both acid-base 2-stage processes (and not the only
ones); you use 1-2 ml sulphuric acid per 100 ml methanol and 1000 ml
WVO, Aleks uses 1 ml sulphuric acid per 100 ml methanol and 1000 ml
WVO, and that's where the similarity ends.

You use 98% plus sulphuric acid, which is expensive, Aleks uses 95%,
which is much cheaper. You seem to mix the sulphuric acid with the
methanol first, Aleks mixes the methanol with the WVO and then adds
the sulphuric acid, which has a quite different effect.

You're metering the first-stage process down to a titration of 2.6,
Aleks doesn't do any titration at all.

You're then using at least 6.4 grams of sodium hydroxide, depending
on titration, Aleks uses 3.1 grams total, regardless of titration.

You're left with glycerine and soaps, which may have to be filtered.
Aleks doesn't have any soaps.

Your method is for high FFA oil or animal fat, Aleks's is for any oil
or fat - it's one standard process, it doesn't use any titration, it
cuts the lye amounts by more than half, it's reliable. Your method
states: "This is not for those who don't like failed batches; the
proportions and process methods are still under experimentation."

Aleks and I knew you'd posted your method on the Maui board in
December, but it didn't seem any different to what you'd posted to
the biofuel list earlier that month following a quite lengthy
discussion of it on the list with Aleks (see "Re: FFA@home-Why NOT?",
7 Dec 2000, etc). Aleks was working with high FFAs and sulphuric acid
well before that anyway.

Best wishes

Keith Addison
Journey to Forever
Handmade Projects
Tokyo
http://journeytoforever.org/


>--- In biofuel@y..., Keith Addison wrote:
> > Good news - no need to bother about FFAs, titration, pH meters and
> > all that stuff, just do it this way, no fuss, very high yields. You
> > saw it here first folks!
> >
> > The FOOLPROOF way to make biodiesel
> >
> > NEW standard method
> >
> > By Aleks Kac
> >
> > Free fatty acid to ester conversion
> >
> > This is a FOOLPROOF way to make biodiesel. No titration is
>required,
> > and no extra equipment -- thermometer optional, and NO pH meter!
> >
> > This is a two-stage procedure, acid first-stage, base second-stage.
> > It is based on the highest FFA content found in used oil, but it
>can
> > be used with any waste vegetable/animal oil or fat (WVO), whether
>or
> > not it has a high FFA content. The process increases yields
> > dramatically. Use it as your standard method.
> >
> > The acid-based phase is universal: it ESTERIFIES and
>TRANSESTERIFIES!
> > The lye-based phase on the other hand is faster but can only do
> > transesterification and makes soap, which we don't like. Acid
>doesn't
> > makes soap.
> >
> > In one test I used a mixture of half heavily used WVO and half pork
> > lard. The result was a pure product with absolutely no trace of
>soap!
> > The esters looked nice, and smelt nice, as if made from virgin oil.
> >
> > Read all about it, full instructions (pictures next week):
> > http://journeytoforever.org/biodiesel_aleksnew.html
> >
> > Enjoy!
> >
> > Keith Addison
> > Journey to Forever
> > Handmade Projects
> > Tokyo
> > http://journeytoforever.org/

To: biofuel@yahoogroups.com
From: Keith Addison
Date: Wed, 7 Feb 2001 07:34:01 +0900
Subject: [biofuel] Fwd: Re: Alek's Recipe

>From: "Kevin Tidball"
>To: "Keith Addison"
>Subject: Re: Alek's Recipe
>Date: Wed, 7 Feb 2001 09:00:59 +1100
>
>Keith,
>
>I'm happy enough with your response, as it identifies the differences.
>
>This allows my work to continue without the threat of someone elses Patent
>appling to my work.
>
>Thank you for your quick response.
>
>Regards Kevin Tidball

Now if one of you two can get it to work using the Dr Pepper technique (Pat Pend) I will be able to get rid of the 299ml of 98% sulphuric acid sitting on top of my pianola.

Tilly SBC/IBA careful pumping div ;

I tried the process Aleks described. I started with 17.4 FFA waste restaurant grease which had been dried and filtered to remove contaminants.
I used 1 liter of oil + 100 ml of methanol and 1 ml of 95-98% sulfuric acid. After mixing for 90 minutes at 55C, I went through the second syep as described and settled for 12 hrs. The FFA level only dropped to 14.2. Obviously some FFA`s have combined with the methanol to make methyl esters but not all of it. What am I doing wrong ?? any thoughts ??
Your help would be appreciated.
Charlie

The acid stage operates slowly so the longer it's left the more FFA it will esterify. Fine, but how do you know how long is enough without titrations?

If the acid reaction is left running for too long it begins to transesterify the tryglyceride oil. Not good because it makes mono and diglycerides. For some reason the later alkali stage doesn't remove these and you end up with dark coloured water retentive biodiesel.

I've tried the "foolproof method" with lightly used oil. I got dark coloured water retentive biodiesel that the car hated. I also had to run a second base stage because for my oil the recipe used too little NaOH.

IMO the process is not foolproof and not suitable for low FFA oils.
1 You must titrate before and after the acid stage otherwise you don't know how long to run the acid reaction or how much NaOH to use for the base stage.
2 Run the acid too long and you get mono and diglycerides.
3 Be very accurate with the acid quantity and later the NaOH quantity used to neutralise. Get that wrong and the base stage will be over or under fed with NaOH.

That all said, with appropriate titrations and calcs along the way acid/base reacted biodesel should be fine. The commercial plants use it without problems.

Do watch out for Alecs warning about methanol and sulphuric acid. Mix the oil and methanol before adding acid. Acid and methanol create toxic fumes.

Looks like Alex is Keith and defended by Todd,Alex cannot respond so Keith does it for him and if anybody disagrees along comes the lap dog Lacky with appalling manners not that the biogod has any, mores the pity.