Made some bio diesel, now what? (Full Version)

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mwright -> Made some bio diesel, now what? (3/1/2003 2:03:30 AM)

A while back I posted a question to see if anyone had made any progress with bio diesel. I work in a Chemistry Department and have done my fair share of organic synthesis so I had no excuses and I just decided to make some. After much, much reading I made a batch of bio diesel.

Here is the short version of what I did: (Two stage method: see http://www.journeytoforever.org/biodiesel_aleks.html )

Stage #1
500 mL Soybean Oil (Plain Crisco Vetable Oil, can use waste oil with some pre-treatment)
125 mL MeOH/1.8 g NaOH
Heat/Stir/1hr@55C
Cool/separate glycerine from FAME (Fatty Acid Methly Ester)

Stage #2
First run FAME
125 mL MeOH/1.8 g NaOH
Heat/Stir/1hr@55C
Cool/separate glycerine from FAME

Wash FAME
3 x 150 mL Saturated NH4Cl
3 x 150 mL Saturated NaCl
3 x 150 mL water
Note: Forms a terrible emulsion when washed, requires time to separate.

Dry FAME
Heat to 130 C for 1 hr

So now I have 400 mL of this stuff, light gold in color (density 0.8597 g/mL and no glycerine by GC-MS).

I am waiting on a Head conversion for an OS 40 FP to test. I found several blends of bio diesel with various oils. I even saw where one person ( http://www.veggievan.org/biodiesel/plane.html ) used 5% chain saw oil!! I suppose I'll start with castor and see if I can really get away with not using ether as some have reported. A person could spend a lot of time just testing their fuel!!!!! I'm open to suggestion for testing.

Marcus

I'll let you guys know



coomarlin -> Re: Made some bio diesel, now what? (3/10/2003 7:28:35 PM)

LOL. You're a hardcore modeler :D Keep us posted on your results.

[QUOTE]Originally posted by mwright
A while back I posted a question to see if anyone had made any progress with bio diesel. I work in a Chemistry Department and have done my fair share of organic synthesis so I had no excuses and I just decided to make some. After much, much reading I made a batch of bio diesel.

Here is the short version of what I did: (Two stage method: see http://www.journeytoforever.org/biodiesel_aleks.html )

Stage #1
500 mL Soybean Oil (Plain Crisco Vetable Oil, can use waste oil with some pre-treatment)
125 mL MeOH/1.8 g NaOH
Heat/Stir/1hr@55C
Cool/separate glycerine from FAME (Fatty Acid Methly Ester)

Stage #2
First run FAME
125 mL MeOH/1.8 g NaOH
Heat/Stir/1hr@55C
Cool/separate glycerine from FAME

Wash FAME
3 x 150 mL Saturated NH4Cl
3 x 150 mL Saturated NaCl
3 x 150 mL water
Note: Forms a terrible emulsion when washed, requires time to separate.

Dry FAME
Heat to 130 C for 1 hr

So now I have 400 mL of this stuff, light gold in color (density 0.8597 g/mL and no glycerine by GC-MS).

I am waiting on a Head conversion for an OS 40 FP to test. I found several blends of bio diesel with various oils. I even saw where one person ( http://www.veggievan.org/biodiesel/plane.html ) used 5% chain saw oil!! I suppose I'll start with castor and see if I can really get away with not using ether as some have reported. A person could spend a lot of time just testing their fuel!!!!! I'm open to suggestion for testing.

Marcus

I'll let you guys know [/QUOTE]



downunder-RCU -> Made some bio diesel, now what? (3/11/2003 7:01:18 AM)

Bio diesel was originally intended for true diesel engines and our engines aren't true diesels so I think it's more like a replacement for the kero that's normally used. But I seem to remember someone trying it and it worked so long as the engine was first started on normal (ether) fuel and then switched over to the bio diesel once the engine had warmed up. Sort of like the old spark ignition tractor engines had to be started on gasoline and then could be switched over to run on kero (in the days when kero was far cheaper than gas).



mwright -> Made some bio diesel, now what? (3/11/2003 7:33:19 PM)

The more I read on this topic (still waiting on my conversion head!!!!) I too see this stuff as a replacement for the kero. Which is not too exciting. I suppose my motivation with using this stuff is just one of exploration. I would like to definitivly lay this stuff aside as a myth or verify it's usefulness. Best case scenario is it requires less ether and oil. And maybe still use silicon tubing. Its kind of fun just tinkering and seeing what works.



Rudeboy -> Made some bio diesel, now what? (3/12/2003 12:40:35 AM)

[QUOTE]Originally posted by mwright
Its kind of fun just tinkering and seeing what works. [/QUOTE]


It's half of the fun...



downunder-RCU -> Made some bio diesel, now what? (3/12/2003 7:43:18 AM)

Keep experimenting and even if it doesn't work satisfactorily then at least you'll be an acknowledged expert on it :D

Maybe it's got a higher heat content than kero so the engine will be more powerful. Maybe it runs at a leaner air/fuel ratio so it's more economical. Maybe it aids lubrication so you can cut down on the amount of normal oil. Who knows? Like Rudeboy says, half the fun with this hobby is trying something different and not just blindly doing what everyone else does :)



rmteo1 -> mwright, would you like to try a diesel conversion head? (3/13/2003 8:45:56 AM)

If you would like to try a diesel conversion head, I make one that will fit most .46 size glo engines from OS, Tower, Mecoa etc. You can try it for FREE. If you are interested, please call or e-mail me. See attached pic.

http://home.earthlink.net/~rmteo/_wsn/page3.html

TS ENGINEERING INC.
1329 Sherman Drive
Longmont, CO 80501
(720) 652-9140
[email]rmteo@earthlink.net[/email]



mwright -> it runs (3/31/2003 7:56:32 PM)

Brief update. I got my Davis conversion for an OS 40FP. Very nice product. I mixed a batch of conventional diesel (20% castor, 30% ether, 2% amyl nitrate, 48% kero). Got it running after following Davis' directions (9200 with an 11x6 APC). It behaved just as he had said in the directions.

Next, I made a biodiesel blend that I suspected would work (10% castor, 30% ether, 2% amyl nitrate, 58% FAME). Had to open up the high speed needle 1 turn at same compression setting (9400 with the 11x6 APC). I'll have some more numbers but I'll wait to see how consistent they are. Just by ear, the biodiesel turns up better. We had some cold weather here (35 to 40 deg F) but it still fired right up and ran well enough to fly a plane. I would have continued but one of fingers was grazed by the prop!!!! Looks like bad "road rash". I used to complain about remote needle valves until last night. Oh yea, it does smell like french firies, much much better than the kero based stuff (exhaust burns my eyes).

I'm going to "learn" how the little 40FP responds to needle/compression changes then start decreasing the % ether. It will be interesting to see how the oil and ether %'s pan out. I trying to not make any assumptions and let the motor tell me what it likes. Please remember I'm just having fun in the back yard and telling you about it.

Marcus



Diesel Dave-RCU -> Made some bio diesel, now what? (4/1/2003 8:52:34 PM)

Marcus,

A few questions. First, I have been flying with os, and Davis heads on all my stuff for about 7 years. I have 5 engines converted, two of which are, well were in a ov-10, before that horrible day, but that is another discussion.

I don't make my own fuels, I just op for either, Kero, or lamp oil, and the Davis fuel mix. I just recently started to use his pre mixed fuels, for simplicity.

Ok, here we go. Your rpm numbers for the conventional fuel mix seems to be a little low. Just how broke in is this motor you are using? I see you mixed your own additive. (the ether, and oils). Is this Davis's recipe, or your own? just for comparison, my FP-40 will turn an 11x7 APC at around 9800 rpm static. And that is running on kero, and Davis supplied mix. The head screw is about 1 1/4 turn out, and the same on the needle. The engine did suffer a flaked cylinder wall 2 years ago. The piston and sleeve were replaced with a Tower hobbies ABC 40 piston sleeve set (NEW). understand both engines are identical, except the sleeve in the Tower is chrome plated, and the OS is nickle plated. all the parts are interchangeable. BTW, the new piston, sleeve, were never broke in on glow, they started their service as a diesel. As time goes on, I expect this engine to go over 10,000 rpm, as it breaks in.

When you ran the FAME, I see you dropped the Castor content, WHY??? Don't take it wrong, but you are giving me the impression that you are playing both sides of the fence, so to speak. It would seem to make this test accurate, you would leave the mix of Castor, either, amyl nitrate, and FAME a constant, and just change the properties of the FAME. I am not a chemist, what am I missing?? In general human language please (GRIN)

Dave



mwright -> answers (4/1/2003 10:50:15 PM)

I will try to answer your questions the best I can;

I agree the RPM's are lower than I expected. The motor is just broken in from running as glow so RPM's may increase some with time. I think it would probably turn up better better on a commercial mix and that may come later.

I see your point that one variable should be changed at a time. This first mix was just to see if the stuff would run, thats all, no more and no less. Concerning the use of less oil, the FAME is very "oily" to start with.

I just want to see how much oil and ether is required to give a good idle, good transistion and top end. That's all, just good, not great performance. Untill I learn a lot more I don't feel comfortable comparing a home brew to a commercial blend. It's like me trying to pick a fight with professional boxer, I know I would lose very, very fast.

Let me kown if you have any suggestions, I'm going to fire it up this afternoon. I think these would be interesting: (doubt I'll get them all done today)

20% oil, 30% ether, 2% AN, 48% FAME
10% oil, 30% ether, 2% AN, 58% FAME
5% oil, 30% ether, 2% AN, 63% FAME

20% oil, 20% ether, 2% AN, 58% FAME
20% oil, 10% ether, 2% AN, 68% FAME
20% oil, 5% ether, 2% AN, 73% FAME

10% oil, 10% ether, 2% AN, 78% FAME
5% oil, 5% ether, 2% AN, 88% FAME



Diesel Dave-RCU -> Re: answers (4/1/2003 11:22:41 PM)

[QUOTE]Originally posted by mwright

20% oil, 30% ether, 2% AN, 48% FAME
10% oil, 30% ether, 2% AN, 58% FAME
5% oil, 30% ether, 2% AN, 63% FAME

20% oil, 20% ether, 2% AN, 58% FAME
20% oil, 10% ether, 2% AN, 68% FAME
20% oil, 5% ether, 2% AN, 73% FAME

10% oil, 10% ether, 2% AN, 78% FAME
5% oil, 5% ether, 2% AN, 88% FAME [/QUOTE]

Well lets do this first, I am sure you know how a "real" diesel runs, but I am going to give a fast explanation anyhow, just for the benefit of anyone else reading this. Basically the engine on the compression stroke, is just compressing air. (this is a real diesel engine, like in a semi truck) In the process of compressing air, you create heat. So much so, that at the top of the stroke, when the fuel is injected, the temperature in the chamber is greater than the flash-point of the fuel, causing the fuel to burn instantly.

I drive trucks for a living. I happen to know that most diesel engines in the industry have a compression ratio greater than 20 to 1 to achieve this.

In a model engine, we don't have a chance at reaching that kind of compression ratio, without a catastrophic failure. This is why the either is in the fuel in the first place. with its much lower flash-point, than kerosene, or FAME in this case, it will start to burn at a compression more realistic for our engines. When the either burns, it in turn starts the kerosene. Either is the igniter, kerosene is the fuel, get it.

I see the lower oil mixes, working well, just because the FAME is so oily already. But the lower either mixes you have listed, I think will cause you lots of trouble. You will definitely have to increase the compression with less either. I would not take the compression any higher than 1/2 to 3/4 turn out, especially on a hot engine. Any more than that, you might break your connecting rod, or at least bend it.

Dave



mwright -> Made some bio diesel, now what? (4/2/2003 12:47:21 AM)

I think you are probably right about the ether. Has anyone ever tried acetone in place of the ether?

Ether: boiling point 35-36 C flash point -40 C
Acetone: boiling point 55 C flash point -18 C



Diesel Dave-RCU -> Made some bio diesel, now what? (4/2/2003 3:11:07 AM)

I don't think anyone has tried Acetone. I don't think it will work either. The ether's boiling point has something to do with it as well. I don't think Acetone would vaporize fast enough to be effective. Would be nice if it does, it is lots easier to get.

I have heard that you can spray starting fluid into your fuel to replace the ether if it has evaporated (IE- if your fuel is old, and not sealed tightly) Starting fluid, from the auto parts store is of course ether, and cetane. I hear that the cetane does not affect the engine. I have never tried it.

Dave



Rudeboy -> Made some bio diesel, now what? (4/2/2003 6:10:05 AM)

I don't know a lot about diesel engines.... but I know how things work and what the function is of the different fuel components...

So:

You say your vegetable oil fuel is very oily...this instinctively tells me it is harder to ignite and will probably burn slower compared to kero. So if you want to experiment with different ether contents, start with a little more ether instead of less...

So your fame is very oily... but will it provide enough lubrication to take the oil content down to 5%...? Tricky... If I were you I'd make sure I have a spare cilinder liner and piston at hand, because your experiment could be over in a hurry with only 5% oil. I'm not saying it won't work, but there's a distinct possibility something will fail.

The acetone part sounds interesting... Give that a try, you might be on to something there... Acetone carries a lot more energy compared to ether, so just maybe there's extra power to be made... Maybe try some 15%ether-15% acetone initially, because I think the engine will get hard to start without ether.


Just my 0.02...



Diesel Dave-RCU -> Made some bio diesel, now what? (4/2/2003 6:30:34 AM)

[QUOTE]Originally posted by Rudeboy
You say your vegetable oil fuel is very oily...this instinctively tells me it is harder to ignite and will probably burn slower compared to kero. So if you want to experiment with different ether contents, start with a little more ether instead of less...

[/QUOTE]

I am starting to think the same thing. That the FAME just does not have the "kick" that the kerosene does. How about a 50, 50 mix of FAME, and Kersoene???

Dave



mwright -> Made some bio diesel, now what? (4/2/2003 8:40:02 PM)

Quick update after 3 hours of mixing and running and mixing and running....

First, 10% oil, 30% acetone, 2% AN, 58% FAME, would not run, nothing at all????

These are all 2% amylnitrate and not the absolute maximum rpms but backed off a little since compressing more gave the pinging sound.


%oil, %ether, %base, rpm, high needle, comp screw
20, 30, 48 kero, 9800, 1.25, 1 turn
20, 30, 38 FAME, 9350, 1.50, 0.75 "
10, 30, 58 " , 9500, 1.25, 1 "
10, 20, 68 " , 9750, 1.35, 1.25 "
10, 10, 78 " , 9300, 2.50, 1 "
10, 5, 83 " , 9300, 3.00, 0.75 "

My observations:
I was able to really find the high rpm region better after runing lots of kero base stuff so I feel a little better about these numbers. You can really tell when you reach 10,000 rpms. I also noted the kero based fuel has a lower exhaust pitch, the FAME sounds more like running glow fuel. The most noticable thing I noted was that with lower ether concentrations the high speed needle had to be opened up more and more. At the lowest ether concentration the idle was high (4k) and I would say it was an unreliable idle and transistion. The 10% oil, 20% ether, 68% FAME was the best FAME run and "felt" equal to the kero based run.
Each run lasted about 7-8 minutes and I repeated each peak seeting several times. One problem I'm having is measuring the volumes with precision, I'd rather do it by weight.

I did not try 5% oil due the risk of failure. The outside temp was 68 deg C and I'm at 750' ASL.

Enjoy!



bobi -> Made some bio diesel, now what? (4/3/2003 9:38:54 AM)

mwright

this is very interesting.

could you also post the idle rpms along with the peak rpm obtained in your study. Prop used ? .
could you also note smoothness of the transition from idle to peak in each case.



mwright -> Made some bio diesel, now what? (4/3/2003 7:26:13 PM)

Prop was an APC 11x6. All idle rpms were about 2000-2200 rpms except for the 5% ether and that idle was about 4000 rpms. Transition from a 10 sec idle was good (equal to glow) for all runs except 10 and 5% ether. Peak rpm's were about 300-200 higher than what was reported, I tried not to over compress.

Update: I got a 10% oil, 25% acetone, 5% ether and FAME mix to run, well kind of. High speed needle was way out, ran rough and required a lot of compression. I definitly see a correlation between ether concentration and richness. Anybody have an idea as to why you need to richen up so much with low ether concentrations?

I have a few more mixes to try for the weekend.

Marcus



Rudeboy -> Made some bio diesel, now what? (4/4/2003 5:04:44 AM)

Beats me...

I thought it was going to be the other way around...



bobi -> Made some bio diesel, now what? (4/4/2003 9:26:41 AM)

ether detonates on compression
lower ether level means it is more difficult to ignite the mixture so that is why your engine will run very poorly as all the fuel is not burnt in the combustion process. To ignite the mixture you have to compensate by increasing the compression ratio or run a richer mixture to get more ether in the process



bobi -> Made some bio diesel, now what? (4/4/2003 9:30:14 AM)

the source of ignition in these engines is the correct ether level....if you are going absolutely down on ether then what is left to ignite the Fame/kero as they do not burn on compression.



Rudeboy -> Made some bio diesel, now what? (4/4/2003 1:19:10 PM)

Makes sense...



mwright -> Made some bio diesel, now what? (4/4/2003 9:42:54 PM)

I concur that contrary to other reports the ether is required with FAME. You may be able to use a little less ether and oil with the FAME.

Ok, here is another mix I think you may find interesting, 10% soybean oil (Crisco veg oil), 20% ether, 2% AN, 68% FAME, it ran and ran well! High needle was 1.5 out and 1 turn compression. Good tranisition and idle. I could touch the head for a few seconds after the run, not too hot at all. Makes me wonder about the need for caster oil with the FAME but then I also think about engine life??? I may mix up a large batch with soybean oil and just let it run at full throttle for a long time and then check for signs of wear and carbon.

These are neat power plants, every motor head should own one.



Diesel Dave-RCU -> Made some bio diesel, now what? (4/5/2003 3:28:55 AM)

Marcus,

I you got one, or be willing to get one, pick up a temperature gun. It would be interesting to see what kind of head temps you are generating. Exhaust temps would be cool too.

I think Tower caries one for the RC car guys..

Dave



mwright -> Dave (4/5/2003 9:40:34 PM)

I agree that kowning head and exhaust temps would keep the guess work to a minimum. The ultralight piolts I've been around really keep a close check on head temps for fear of scorching a pistion in a lean run.

I think the temp guns are not too expensive ~$70-80. I should just quit my day job and blend fuel... don't think the wife and three kids would take well to that idea.

Take care.

Marcus



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