Question:
>>Yup, the Austrians have had several plants running for ages. There are several >plants that produce 500t/pa of rapeseed oil methyl esters and one that produces >10,000 t/pa and 1992 they were building a 15,000t/pa plant. >Wow! Is this economical there? Or is it done to support farm incomes? >It would supprise me to find out that it was at economic break-even… >and Europeans do have this tendency to do non-economic things for >social policy reasons…
As I noted earlier, the NZ trials showed tallow esters were viable at $27/bbl crude oil, but that’s highly dependant on the glycerol price. In fact the glycerol price can actually cover all the production costs, and so the esters become a valuable byproduct 
. I suspect this may be the case in Europe. Certainly one series of NZ trials demonstrated that methyl esters were very cost-competitive with diesel. There have also been other ester fuel trials in Europe ( France) which do seem to benefit from CAP. They were discussed in New Scientist a couple of years ago. … >MAGs have 2 OH groups, they aren’t greatly soluble in Esters. >They are high melting point solids… >Hmmm… I was working with an oil, rather than a fat. I suppose >that the solid vs liquid for MAGs would be a function of the starting >fatty acids, the minium temp, and the added OH groups… I’ll >have to stick some ‘product’ in the freezer and see what I get 
The part I quoted was from a report on vegetable oil methyl esters, and they will have a different FAME profile to the NZ trials of tallow, which will affect the separation temperature, but most low-cost oils do have significant amounts of C16 or C18 saturated fatty acids in them. I suspect some vegetable oil esters may be able to cope with % levels of MAGs,DAGS, and TAGs. > Now if only Soybean oil didn’t cost me $3/gallon at the local discount >store…
Why no try and get some waste cooking oil from a local fast food/restaurant? Bruce Hamilton
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>> Now if only Soybean oil didn’t cost me $3/gallon at the local discount >store… >Why no try and get some waste cooking oil from a local fast food/restaurant?
What? Put *USED* oil in my Mercedes Benz?! What kind of person do you think I am? ;-) The ‘real answer’ is that I’m just experimenting at this and want to have controled and repeatable results. I like getting the oil in convenient clean jugs that take no treatment to remove bits of french fries and fish breading. If I ever decided to do this on a regular basis, then I would investigate ‘alternative’ sources… — E. Michael Smith Manager of Stuff Cygnus Support
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>Yup, the Austrians have had several plants running for ages. There are several >plants that produce 500t/pa of rapeseed oil methyl esters and one that produces >10,000 t/pa and 1992 they were building a 15,000t/pa plant.
Wow! Is this economical there? Or is it done to support farm incomes? It would supprise me to find out that it was at economic break-even… and Europeans do have this tendency to do non-economic things for social policy reasons… >How? I could not get ethyl or iso-propyl esters to form >at room temp with NaOH. Did I not wait long enough or blend >well enough?
Below this is answered… I was doing it to cold … and too long. – Hide quoted text — Show quoted text ->If the sample is dry, the methanolysis >is significantly faster, but if the reaction is continued for too long the >hydrolysis can dominate. >>Their advantage over the pure oil is in the life of a >>modern diesel engines – experience has shown that using >>triglycerides can result in abnormal fuel/lubricant >>interactions that lead to early engine failure. >Hmmm… What kind of ‘interactions’? If there is a report >on this as well, I’ll just order it… >The quick and diry answer is … >have shown that the presence of TAGs and partial glycerides and partial >glycerides in the fuel causes serious problems through formation of engine >deposits: carbonization of the injection nozzle,piston, and valves, and >formation of sludge in the lubrication system have been reported [ Energy
YUCK. Guess I'll limit myself to modest usage levels for a while ... Then again, I change my oil rather often and would be alternating esters with #2 Diesel, so maybe carbonization would not be very bad after all... Hmmm, more Experimentation! >>The problem ( its mentioned above ) is the removal of >>monoacylglyccerides, and much of the process optimisation >Why do you need to remove them? (And what conditions favor >their formation?) If it is just phase separation, then I'd >think finding an additive to keep the phases mixed would be >as easy or easier a solution?
Since the problem is in the combustion of the stuff, keeping it mixed would be a mis-feature; as you have shown... Thanks for the good info on other catalysts! Potassium carbonate is often available here for swimming pool pH adjustment... >Both sodium hydroxide, and sodium methoxide dissolve in MeOH.
I'll have to try this. I just dumped the NaOH into the pot and the crystals sunk through the MeOH into the oil. Then stirred. They never did appreciably 'disolve'... >None of the catalysts would give >99% conversions without the glycerol >phase being separated. If you wish to extend diesel, then the product has >to be about 99.9+% pure.
Guess I got pretty good product, since it was completely miscible with some #2 ... >>work in the above reports is focussed on that. The >>presence of MAGs can result in temperature-related separation >>that blocks fuel systems. >Hmmm... why does it 'block' the fuel system? Is it not a >flamable liquid? ... >MAGs have 2 OH groups, they aren't greatly soluble in Esters. >They are high melting point solids...
Hmmm... I was working with an oil, rather than a fat. I suppose that the solid vs liquid for MAGs would be a function of the starting fatty acids, the minium temp, and the added OH groups... I'll have to stick some 'product' in the freezer and see what I get Having fuel gel in the fuel line is not fun... but a rare problem in California... I think I'd like to keep it rare >I'm somewhat interested in knowing what reaction conditions are >needed to make ethyl and iso-propyl esters. Any info? >In general the increase C1,C2,C3, requires more aggressive conditions,
Which explains why I got nowhere, since I used identical conditions... and far too long a time. I'll try again in a few (days? weeks? months?) with more aggression... >It takes about 20 minutes with sporadic simple stirring. Maybe >I'll try heating and blending with ethanol ... >The important point is to ensure the glycerol easily separates, >and that the reaction doesn't go too far,
I think I learned this the hard way... I let some sit overnight and things got 'icky'... Less product and more junk in it... especially a soap mixed with 'stuff' layer/problem. >you can add hot water >to stop the reaction..
Nice tip! >The iso-propanol was completely disolved in the cooking oil, so >I think there was something other than mixing involved in getting >it to react... >Sure, but the rate of the reaction is dependent on temperature >( 50-60C about right, ratio of catalyst ( usually given as a mass% of the >triglyceride), regardless of the solvent, and 3 moles of methanol,are required
I was trying to make isopropanol 'go' at room temp... I'll try modest heat next time... and with poor mixing of the NaOH. >>there should be no fatty acids to make soap. >Ah, but given the choice of 'disposing of a lye waste stream' >and reacting it with a bit more oil to make some soap product ... >I think I'll take the soap as a safer more valuable alternative. >That's not the choise, the problem is the soaps will increase the >dissolution of undesirable impurities in the esters.
We have a difference of premises here... Since I was being left with an un-dissolved lye layer on the bottom (due to mild stiring the mix and NOT mixing the lye with the MeOH first...) I was presuming that a partly saponified solid lye layer was a normal 'waste product' after you decanted the product and the glycerol layer... And I would rather make useful soap out of that waste solid lye layer than just chuck it in the trash... But you have enlightened me to the fact that the NaOH is mixed first with the MeOH, and this isn't left lyeing around (groan!) to dispose of at the end of the reaction... Well, thanks for all the info! Next time I make a batch, I'll try mixing the NaOH with the MeOH prior to adding that to the oil. It seems that careful mass ratios of reactants and watching the phase separation over about 20 minutes at room temp (shorter if hotter) gives a pretty good idea when to decant the reactant and also seems to give pretty good product. Now if only Soybean oil didn't cost me $3/gallon at the local discount store... -- E. Michael Smith Manager of Stuff Cygnus Support
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My name is Duncan Grove. I am a first year engineering student at Adelaide Uni. We have a Design Project to find the cheapest way to commute using a modified production automobile. The limitations are basically: (1) This car must be refuelled at (home) the top of a hill, (2) And travel 15km downhill (change in alt: 750 metres) and then 10 km along a plain. (3) The car must then be able to make it back up the hill. (4) Find the cheapest solution to do this 10 (years) x 52 (weeks) x 5 (days) = 130000km We have looked at many (combinations) of power sources, including: Hydrogen, batteries/capacitors/generators for electric motors, Compressed air, Flywheels, organic waste => natural gas, diesel, solar, and many others. We suspect the car will weigh in the neighbourhood of 7-800kg (with 2 passengers). However, most of the printed literature available is over ten years old, and (wrongly) predicted the commuting world would be run on hydrogen or electricity by now... I would be overjoyed to reicieve ANY AND ALL information you have and could send me regarding efficient (and initially cheap(ish)) fuel sources for vehicles. Leads to other information on the internet concerning alternative fuel vehicles would also be fantastic. THANKYOU THANKYOU THANYOU (in advance) for any info or pointers. Please, no replies to this email address... Either post them if you consider it worthwhile, or reply to: Regards -- Duncan Grove.
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>My name is Duncan Grove. I am a first year engineering student at >Adelaide Uni. We have a Design Project to find the cheapest way to >commute using a modified production automobile. The limitations are >basically:
Well, I'd suggest an old VW Diesel Rabbit running on used cooking oil. It gets about 50 mpg on #2 Diesel... In the US, a Diesel truck was recently driven across the nation on used french fry oil... Since restaurants typically PAY someone to take this oil away, you might be able to turn a PROFIT (!). There have been VW Rabbits run on the oil as it comes from a simple filtration step. I've run Soybean, though it smoked at idle in my vehicle. For reasons that were not stated, the Van folks decided to convert the cooking oil via a trans-esterification process. I'd guess that they were making the viscosity a closer match to that of #2 Diesel. Fats and oils are a glycerine backbone with three fatty acids hooked on via an ester bond. Trans-esterification moves those ester bonds onto other alcohols. What the news said they did with the Van was to mix 80% (filtered to remove french fry bits!) cooking oil with 19% methanol with 1% lye (sodium hydroxide) to convert the oil to methyl-esters. They implied it was just mix and wait... I've not tried this yet, but I will (GRIN). I've made soap before by mixing NaOH and Fat and waiting. It does work. It is also possible to do a trans esterification with a metal hydroxide 'catalyst'.. But I didn't think it could be run at room temperature. Maybe it is because methanol is more reactive? Anyway, the left over Na should just make a few stray soap molecules that would burn just fine, so you might want to try it. At any rate, with methanol being Very Cheap and the used cooking oil being a potential negative cost, you should have very low fuel costs... If the oil works 'straight' for your engine, you could skip the trans-esterification. >(1) This car must be refuelled at (home) the top of a hill, >(2) And travel 15km downhill (change in alt: 750 metres) and then 10 km > along a plain. >(3) The car must then be able to make it back up the hill.
No problem for the VW to do that! >(4) Find the cheapest solution to do this 10 (years) x 52 (weeks) x 5 > (days) = 130000km
It should be hard for the competition to beat a negative cost ... >We have looked at many (combinations) of power sources, including: >Hydrogen, batteries/capacitors/generators for electric motors, Compressed >air, Flywheels,
For cost, all of these will be losers. >organic waste => natural gas,
Maybe, if you ignore the capital costs... >diesel,
THIS is your winning powerplant. You just have to pick your fuel... >solar,
Costly! >and many >others. We suspect the car will weigh in the neighbourhood of 7-800kg (with >2 passengers). >I would be overjoyed to reicieve ANY AND ALL >information you have and could send me regarding efficient (and initially >cheap(ish)) fuel sources for vehicles.
For cheap fuel, you either need to used waste organics (wood, grass, etc.) or discarded cooking oil. >Leads to other information on the >internet concerning alternative fuel vehicles would also be fantastic.
Don't forget the public library... There is a book you need to read. "Methanol and Other Ways Around the Gas Pump". From the early '70s. It has a good treatment of some historical fuel oddities. Of particular note is the nice job it does of documenting the 'gasogene' of WWI and WWII. This is a big iron pot you put {wood, coal, dry grass, paper, dry dung, etc.} into and burn under oxygen poor conditions to get a mix of CO and H2 gasses. These can be ducted into the air intake of a Diesel for combustion... (Or a spark ignition engine, but why bother with the fuss of building a CO gas carberetor when a straight pipe into the diesel air intake is all you need...). BTW, you can see one of these in one of the "Mad Max" films I think it was ... Well, some Sci-Fi type flick where the bad guys have taken over society and they drive around in old wreckers with this big smoking pot on the back ... And there were scantly clad women who ran the civil society (or was that a bad cartoon?...) anyway, you see them from time to time in the movies... A particularly nice vehicle would have a Diesel engine running on used french fry oil and with a gasogene to use any plant type garbage that was laying around... Look up 'producer gas' or 'water gas' in your chemistry texts... It would look really neat to pull up to a garbage can (ala "Back To The Future") and 'top up' your fuel tank with a selection of old newspapers, wood chips, junk mail, and lawn clippings... Gee ... now if someone PAYS you to trim their trees and PAYS you to take the french frier oil ... I like this negative cost fuel idea! -- E. Michael Smith Manager of Stuff Cygnus Support
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writes: >My name is Duncan Grove. I am a first year engineering student at >Adelaide Uni. We have a Design Project to find the cheapest way to >commute using a modified production automobile.
The simplist, lowest cost approach is to use SNG. You modify the carboator (sp) the same as with LNG or propane, but put a small gassifier in the trunk or on a trailer. This approach has been demonstrated many times. Swedan used it to run busses during WWII. In the mid '80's Populer Machanix or Popular Science sponsored a car that ran from NY to LA on scrap wood and garbage.
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>In the US, a Diesel truck was recently driven across the nation on >used french fry oil... ... >What the news said >they did with the Van was to mix 80% (filtered to remove french fry >bits!) cooking oil with 19% methanol with 1% lye (sodium hydroxide) >to convert the oil to methyl-esters. They implied it was just >mix and wait... I've not tried this yet, but I will (GRIN).
Tried it last night. It would seem to work at room temperature in about 20 minutes. I used a concentrated water/lye solution in one trial and used the lye crystals directly in another. Both made product. The lye solution was blended with the methanol, then stirred into the oil. This reacted fairly quickly (and made the typical soap bubbles when stirred along with clouding up like oils do when saponified with lye). The end product had what looked like a non-disolved soap film floating on top of a layer of what I believe was the methyl-esters and a bottom layer of what looked like un-reacted cooking oil. The lye crystals were stirred into a cup of oil/methanol. The liquids were in two separate phases (layers). It looked like not much was happening, but slowly (with stiring) it formed a layer of what looked like thin cooking oil (less cloudy than the product from the lye liquid sample) that was the methyl-ester layer (or at least that is what I presume it was...). It, too, had a small layer of what looked like un-reacted cooking oil on the bottom. But it ALSO had what looked like pretty much ALL of the NaOH crystals still undisolved on the bottom of the cup. The suspected product was tested for flamability (it was much less flamable than methanol, which had been the top layer before reacting...) and a visual inspection showed it to be less viscous than the cooking oil. A tactile examination showed it to be thiner and less oily to the touch. The methanol 'bite' was gone from the odor (sniff with CAUTION! Methanol is toxic, so snort it out as soon as you smell any!). The suspected excess cooking oil was subjected to additional methanol and it seemed to react away to make more 'product'. This was done with excess methanol. In this case a methanol layer remained on the top (confirmed by smell and flamability), along with a lye crystal layer on the bottom, with 'product' in the middle. It would seem that there is a bit more work needed to find the best proportion of methanol to cooking oil for any given oil... The observed viscosity seemed closer to that of #2 Diesel and the observed tendency to burn/smoke when subjected to flame was better than cooking oil (more burn, less smoke...). When I've got the time, I'm going to try this with 5 gallons of cooking oil and some racing fuel methanol, then do a long run in the ol' Benz ... >I've made soap before by mixing NaOH and Fat and waiting. It does >work. It is also possible to do a trans esterification with a >metal hydroxide 'catalyst'.. But I didn't think it could be run >at room temperature.
It would seem that it does run at room temp. Though when first tried with refrigerated oil it either didn't run, or was a very slow reaction. Warmed to room temp it went fast enough. >Maybe it is because methanol is more >reactive?
Also on my 'todo' list is to try it with anhydrous iso-propanol and ethanol... >Anyway, the left over Na should just make a few stray >soap molecules that would burn just fine, so you might want to try it.
The soap only seems to form if a water solution of NaOH is used. The direct use of the crystals seems to not form soap. I have no idea which would be better at this point... >At any rate, with methanol being Very Cheap and the used cooking oil >being a potential negative cost, you should have very low fuel costs...
It would seem that transesterification of plant oils with methanol is a damn near trivial process. Since methanol can be made dirt cheap from your choice of natural gas, coal, wood, garbage, etc. it would seem that synthetic diesel fuel will be cheap and available for many centuries to come. Since nuclear process heat can be used to make the methanol production from coal even cheaper ( about the same on a $/BTU basis as gasoline in the USA) it would seem that the only limit on fuel is the availability and price of biological oils as a fatty acid source ... I'm also going to start looking at alternatives (synthetic from coal with nuke heat) to the oil derived fatty acids used in making the esters... -- E. Michael Smith Manager of Stuff Cygnus Support
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>used french fry oil... Since restaurants typically PAY someone to >take this oil away, you might be able to turn a PROFIT (!).
This may be a misconception - the "yellow grease" is not worhtless. It is used as an additive for animal feed, for one thing.I remember an article in J Am Oil Chem Soc about 4 years ago about "grease rustlers" who were sneaking up behind McDonalds in Texas and draining the grease cans. So, you may want to check into this. Carrie -- Carrie Schneider, Ph.D. National Renewable Energy Lab 1617 Cole Boulevard Golden, CO 80401 303-384-6119
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>>used french fry oil... Since restaurants typically PAY someone to >take this oil away, you might be able to turn a PROFIT (!). >This may be a misconception - the "yellow grease" is not worhtless.
It isn't worthless to the folks who collect it, but it is worthless to the restaurant. We used to pay the local rendering company to come pick up our can once a month. They want to be paid to do this since: 1) The labor cost and truck cost is high. 2) They KNOW you have to dispose of it 'properly' and have no choice. 3) The small lot that any one restaurant has is not worth anything to the purchasers of recycled fats. (i.e. it isn't a big enough lot for you to sell directly to Dr. Ross Dog Food Company...) >It is used as an additive for animal feed, for one thing.I remember
And made into soap and many and sundry other products. The rendering company cleans up the fat, blends it with lots of other fat from the region's restaurants, and sells it in large shipments to feed and soap companies. Only after collection and cleaning does it have 'value' on the market... >an article in J Am Oil Chem Soc about 4 years ago about "grease >rustlers" who were sneaking up behind McDonalds in Texas and >draining the grease cans. So, you may want to check into this.
The restaurant signs a contract with the rendering company. The company owns the cans. If they come to get the grease (spending labor and vehicle costs) and get none, they get pissed and tell the local police that they wan't the folks who are stealing their raw materials caught. This doesn't change the fact that the restaurant pays the renderer to haul the 'garbage' away... I would NOT advocate 'grease rustling', but DO advocate asking your local restaurant owner if they would like a new, free, contract ... Maybe if the market gets competitive enough the restaurant could, in fact, start to get some money for their grease. (We were in a small farm town and had a choice of exactly one rendering company...) -- E. Michael Smith Manager of Stuff Cygnus Support
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Much good stuf deleted... : The suspected excess cooking oil was subjected to additional methanol : and it seemed to react away to make more 'product'. This was done : with excess methanol. In this case a methanol layer remained on the : top (confirmed by smell and flamability), along with a lye crystal : layer on the bottom, with 'product' in the middle. : It would seem that there is a bit more work needed to find the best : proportion of methanol to cooking oil for any given oil... : The observed viscosity seemed closer to that of #2 Diesel and the : observed tendency to burn/smoke when subjected to flame was better : than cooking oil (more burn, less smoke...). : When I've got the time, I'm going to try this with 5 gallons of : cooking oil and some racing fuel methanol, then do a long run : in the ol' Benz ... An outstanding report! Please keep the info coming --
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>>What the news said >they did with the Van was to mix 80% (filtered to remove french fry >bits!) cooking oil with 19% methanol with 1% lye (sodium hydroxide) >to convert the oil to methyl-esters. They implied it was just >mix and wait... I've not tried this yet, but I will (GRIN).
This has been around for ages. Anyone really interested in this should contant the NZ Liquid Fuels Management Group ( PO Box 17 Wellington N.Z.) as they financed several large scale technical evaluations and fleet trials of various esters in the 1970s. Much of the work was performed by DSIR staff who now belong to Industrial Research Limited, if anyone has serious technical questions I can ask some of the authors.... Some report references LF1199 Properties of Tallow Ester/Diesel Fuel blends LF1200 Tallow Ester standard Samples ( for preparing blends ) LF1201 Tallow Ester/Diesel properties LF1202 The use of adsorbents to remove monoacylglycerides from Tallow LF1203 Properties of Tallow Ester/Diesel Blends ( v Diesel ) LF1204 Additive package for tallow esters. LF1205 Soution stability of Tallow Ester/Diesel Blends LF1206 Properties of Rapeseed Oil LF1207 Engine Validation tests on Tallow Ester/Diesel Blends LF1208 The production of tallow ester/diesel blends LF1209 10% Tallow methyl ester/gas oil fleet field trial LF1210 Report on rapeseed methyl ester trials. The economics can be greatly helped by the recovery and resale of the glycerol. It doesn't really matter what aminal or vegetable triglyceride is used as the starting material ( most have 16-24 carbon fatty acids. For the shorter chain ones ( butter starting at C4, coconut about C6 ) then either the ethyl or butyl esters were prepared. The ethyl ester of butter has a beautiful pineapple aroma. As glycerol prices can be cyclic, it's hard to guess what the break-even price is, but in the above studies it was found to be at US$27/bbl crude oil. Their advantage over the pure oil is in the life of a modern diesel engines - experience has shown that using triglycerides can result in abnormal fuel/lubricant interactions that lead to early engine failure. Other problems concerning viscosity and gums were also experienced. NZ decided to concentrate on esters as the engines lasted much longer without maintenance. The problem ( its mentioned above ) is the removal of monoacylglyccerides, and much of the process optimisation work in the above reports is focussed on that. The presence of MAGs can result in temperature-related separation that blocks fuel systems. All of the Ester/diesel trials had successful outcomes, with no observable adverse effects and blends of 10-20% in diesel still met all the diesel specs ( esters have a high Cetane number ). Higher blends and pure Esters ( methyl, ethyl, butyl - for some reason propyl alcohols weren't cost-effective ) worked as well, but they weren't investigated much because we couldn't have produced enought triglyceride. Once the MAGs have been removed, and an additive package added to prevent thermal oxidation and biological deteriation ( same package as already used in diesel ), the properties, storage stability, and engine life matched or exceeded diesel, with improved emissions. >work. It is also possible to do a trans esterification with a >metal hydroxide 'catalyst'.. But I didn't think it could be run >at room temperature. >It would seem that it does run at room temp. Though when first >tried with refrigerated oil it either didn't run, or was a very >slow reaction. Warmed to room temp it went fast enough.
In fact we routinely make liter quantities of esters for animal, veegetable and fish oil fats. The reaction can be performed at ambient temperature in six minutes, if a _really good_ mixer is available, but warming the reaction to about 50C helps a lot. >Maybe it is because methanol is more reactive?
No, it's mainly to do with viscosity, mixing, water content, and ratio of components, obviously the "reaction rate doubles for every 10C increase" rule also has a significant effect. The important point is to avoid the production of soaps, as they will give separation problems between the lower glycerol layer and the upper ester layer, and they represent lost product. Note that there is a huge amount of literature on using esters in CI engines. They have been used in Europe for decades, and NZ focused on Tallow because the europeans had covered most of the vegetable oils. The economics are based on the glycerol product and the alternative value of the feed, along with the cost of disposing of the waste streams - if the process is performed correctly, the only valuable products are the esters and the glycerol, there should be no fatty acids to make soap. For an engine to be run long term on them, then an additive package to prevent bug growth would be required. Bruce Hamilton
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>Much good stuf deleted...
Thanks! >: The suspected excess cooking oil was subjected to additional methanol >: and it seemed to react away to make more 'product'. This was done >: with excess methanol. In this case a methanol layer remained on the >: top (confirmed by smell and flamability), along with a lye crystal >: layer on the bottom, with 'product' in the middle.
An addendum: When left to sit overnight, the lye crystal layer seems to swell and become more waxy looking. When subjected to tactile examination (i.e. when you stuff you hand in it while preparing to wash the sucker...) it IS waxy. It is also soluable in water making a slighly milky solution and suds. i.e. It's soap First Conclusion: Don't leave the lye in overnight or you just waste lye. Second Conclusion: Any excess lye in the product (dust specks...) will react to make soap that is an OK lubricant and relatively neutral chemically. Another addendum: When reacted with excess methanol, and left to stand for a long time (day or two) you get a light layer of 'product' on top that seems to be relatively good Diesel fuel analog and a heavy layer of 'stuff' on the bottom that looks thicker and almost like yellow cooking oil. But it was thicker than the original oil. Flame tests showed an alcohol flame (after some heating). Driving off the alcohol (i.e. watching the pretty colors until the flame goes out left behind a sticky residue that was water soluable with milky solution and suds. More soap Third Conclusion: Excess methanol, unlike excess lye, hangs around. You don't want excess methanol in your Diesel injectors, so don't use excess methanol when making methyl-esters... Fourth Conclusion: Heavy layers on the bottom can NOT be concluded to be left over un-reacted cooking oil, since they may just be an alcohol solution of soap. >: It would seem that there is a bit more work needed to find the best >: proportion of methanol to cooking oil for any given oil...
I vote for excess oil... since you do not want left over methanol in the fuel and since any excess NaOH will become soap. Oh, and in an excess of oil, the left over oil can be easily reacted in the next batch. >: When I've got the time, I'm going to try this with 5 gallons of >: cooking oil and some racing fuel methanol, then do a long run >: in the ol' Benz ...
I've bought the Soybean oil. Now I'm looking for a few gallons of methanol... >An outstanding report! >Please keep the info coming
Why, thank you ( BLUSH !) More info: I got some anhydrous iso-propanol from the pharmacy. It is completely soluble in the soybean oil. It also does not react. The lye crystals are not prone to forming soap either. It would seem that isopropanol is not a candidate for room temperature reaction with NaOH catalyst. I got some pure ethanol from the pharmacy as well (denatured, but anhydrous). It, too, did not react. It also did not disolve in the cooking oil. The lye crystals DID form soap overnight. There was a slight indication of contamination of the alcohol and/or cooking oil with some minor amount of 'reactant'. I don't know if this was from the denaturant, or if the ethanol does make ethyl-esters, but just at so slow a rate that the NaOH ends up in soap before much can be made... And I'm not willing to wait days and days and ... I think there is the potential to use ethanol, given some book time looking for reaction rates and favorable conditions (heating?). In Conclusion: It looks like the 'best' process (so far!) is to use an excess of cooking oil (I'd suggest about 15% by mass of methanol) and crystalline lye; mixed and left to stand for about 1 hour; with a stirring or shakeing every 10 minutes or so. Then decant the product and any left over cooking oil, and start a new batch. Discard the lye at the end of the day (or go ahead and let it sit overnight to make soap. It wasn't half bad soap ... ;-) Next: Making a BIG batch and driving to work on it. Probably next weekend's project ... 'Kitchen Science' is Soooo much fun -- E. Michael Smith Manager of Stuff Cygnus Support
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>>>What the news said >>they did with the Van was to mix 80% (filtered to remove french fry >>bits!) cooking oil with 19% methanol with 1% lye (sodium hydroxide) >>to convert the oil to methyl-esters. They implied it was just >>mix and wait... I've not tried this yet, but I will (GRIN). >This has been around for ages.
Yes, it has. I just didn't realize how easy it is! >Anyone really interested in this >should contant the NZ Liquid Fuels Management Group ( PO Box 17 >Wellington N.Z.) as they financed several large scale technical >evaluations and fleet trials of various esters in the 1970s.
I'll do that. Can I order a generic list of reports, or is it necessary to order each one by report number? >For the >shorter chain ones ( butter starting at C4, coconut about >C6 ) then either the ethyl or butyl esters were prepared.
How? I could not get ethyl or iso-propyl esters to form at room temp with NaOH. Did I not wait long enough or blend well enough? >Their advantage over the pure oil is in the life of a >modern diesel engines - experience has shown that using >triglycerides can result in abnormal fuel/lubricant >interactions that lead to early engine failure.
Hmmm... What kind of 'interactions'? If there is a report on this as well, I'll just order it... >Other problems concerning viscosity and gums were also >experienced. NZ decided to concentrate on esters as >the engines lasted much longer without maintenance.
And given how trivial they are to make, it seems like a Real Good Idea. >The problem ( its mentioned above ) is the removal of >monoacylglyccerides, and much of the process optimisation
Why do you need to remove them? (And what conditions favor their formation?) If it is just phase separation, then I'd think finding an additive to keep the phases mixed would be as easy or easier a solution? >work in the above reports is focussed on that. The >presence of MAGs can result in temperature-related separation >that blocks fuel systems.
Hmmm... why does it 'block' the fuel system? Is it not a flamable liquid? ... >( esters have a high Cetane number ). Higher blends and pure >Esters ( methyl, ethyl, butyl - for some reason propyl >alcohols weren't cost-effective ) worked as well, but >they weren't investigated much because we couldn't have produced >enought triglyceride.
I'm somewhat interested in knowing what reaction conditions are needed to make ethyl and iso-propyl esters. Any info? >It would seem that it does run at room temp. Though when first >tried with refrigerated oil it either didn't run, or was a very >slow reaction. Warmed to room temp it went fast enough. >In fact we routinely make liter quantities of esters for animal, >veegetable and fish oil fats. The reaction can be performed at >ambient temperature in six minutes, if a _really good_ mixer is >available, but warming the reaction to about 50C helps a lot.
It takes about 20 minutes with sporadic simple stirring. Maybe I'll try heating and blending with ethanol ... >>Maybe it is because methanol is more reactive? >No, it's mainly to do with viscosity, mixing, water content, and >ratio of components, obviously the "reaction rate doubles for >every 10C increase" rule also has a significant effect.
The iso-propanol was completely disolved in the cooking oil, so I think there was something other than mixing involved in getting it to react... >The important point is to avoid the production of soaps, as >they will give separation problems between the lower glycerol >layer and the upper ester layer, and they represent lost >product.
Yup. That is what I found in the 'let it sit overnight' trials... you get more soap, and more layers of mixtures of stuff that you didn't want mixed. Like a soap/glycerol/methanol layer... >Note that there is a huge amount of literature on using esters >in CI engines. They have been used in Europe for decades, and >NZ focused on Tallow because the europeans had covered most of >the vegetable oils.
Guess it's time to hit the library again... >The economics are based on the glycerol >product and the alternative value of the feed, along with the >cost of disposing of the waste streams - if the process is >performed correctly, the only valuable products are the esters >and the glycerol,
This is fine. >there should be no fatty acids to make soap.
Ah, but given the choice of 'disposing of a lye waste stream' and reacting it with a bit more oil to make some soap product ... I think I'll take the soap as a safer more valuable alternative. >For an engine to be run long term on them, then an additive >package to prevent bug growth would be required.
I'm thinking of blending it 50/50 with #2 Diesel and just depending on the additives in the #2 to keep the bugs down... At least for occasional use... -- E. Michael Smith Manager of Stuff Cygnus Support
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>>This has been around for ages. >Yes, it has. I just didn't realize how easy it is!
Yup, the Austrians have had several plants running for ages. There are several plants that produce 500t/pa of rapeseed oil methyl esters and one that produces 10,000 t/pa and 1992 they were building a 15,000t/pa plant. >Anyone really interested in this >should contant the NZ Liquid Fuels Management Group ( PO Box 17 >Wellington N.Z.) as they financed several large scale technical >evaluations and fleet trials of various esters in the 1970s. >I'll do that. Can I order a generic list of reports, or is >it necessary to order each one by report number?
You will have to specify the report number. I suspect the reports will also be available in the US, and the copy of the final Liquid Fuels Trust Board report LF 6020 has an ISBN of 0-478-00407-9. If you have too many problems, email me, our library will have some of the them. They may be filed under the Liquid Fuels Trust Board rather than LFMG. >For the >shorter chain ones ( butter starting at C4, coconut about >C6 ) then either the ethyl or butyl esters were prepared. >How? I could not get ethyl or iso-propyl esters to form >at room temp with NaOH. Did I not wait long enough or blend >well enough?
There are two competing reactions, the methanolysis and the hydrolysis. If water is present ( used cooking oils are partially oxidised, and do tend to dissolve more water. If the sample is dry, the methanolysis is significantly faster, but if the reaction is continued for too long the hydrolysis can dominate. >Their advantage over the pure oil is in the life of a >modern diesel engines - experience has shown that using >triglycerides can result in abnormal fuel/lubricant >interactions that lead to early engine failure. >Hmmm... What kind of 'interactions'? If there is a report >on this as well, I'll just order it...
The quick and diry answer is in the Journal of High Resolution Chromatography v15 p609-612. Sept 1992 "Quality Control of Vegetable Oil Methyl Esters used as Diesel Fuel Substitutes : Quantitative Determination of Mono-,Di-, and Triglycerides by capillary GC " Christina Plank & Eberhard Lorbeer. "Since incomplete tranesterification of vegetable oils can lead to significant contamination of the vegetable oil methyl esters with MAGs,DAGs and TAGs, continuous quality control of the product is essential. Long term engine tests have shown that the presence of TAGs and partial glycerides and partial glycerides in the fuel causes serious problems through formation of engine deposits: carbonization of the injection nozzle,piston, and valves, and formation of sludge in the lubrication system have been reported [ Energy in Agriculture v2 ( 1983 ) p369 ]. The incomplete combustion of glycerides also leads to the formation and emission of hazardous acrolein, derived from glycerol. In Austria, a limit to the permissible levels of MAGs,DAGs, and TAGS in rapeseed methyl esters has been introduced in std ONORM C 1190…." This is slightly different to NZ where we specified 0.05%max. MAG. … >The problem ( its mentioned above ) is the removal of >monoacylglyccerides, and much of the process optimisation >Why do you need to remove them? (And what conditions favor >their formation?) If it is just phase separation, then I’d >think finding an additive to keep the phases mixed would be >as easy or easier a solution?
No, it’s far more complex than that – you have to balance the reaction such that esters are favoured. Remember that you _want_ phase separation to remove the glycerol phase. There are three possible economic catalysts for the tranesterification. -Potassium carbonate, good phase separation, slower and the reaction doesn’t seem to go as far. -Sodium Methoxide, the method favoured by industry, and the mechanism is identican to NaOH. Current safety rules may adversely affect this choice. – Sodium Hydroxide, can provide pure produvct in one batch step ( compared to two for the above ). Timing is critical and it has the worst phase separation characteristics. It is the cheapest, so as long as the reaction is controlled it works OK, but it will produce the most soar ( highly undesirable as it can contaminate the product with unwanted products.). Both sodium hydroxide, and sodium methoxide dissolve in MeOH. None of the catalysts would give >99% conversions without the glycerol phase being separated. If you wish to extend diesel, then the product has to be about 99.9+% pure. >work in the above reports is focussed on that. The >presence of MAGs can result in temperature-related separation >that blocks fuel systems. >Hmmm… why does it ‘block’ the fuel system? Is it not a >flamable liquid? …
MAGs have 2 OH groups, they aren’t greatly soluble in Esters. They are high melting point solids… >I’m somewhat interested in knowing what reaction conditions are >needed to make ethyl and iso-propyl esters. Any info?
In general the increase C1,C2,C3, requires more aggressive conditions, they are feasible, but as C1 works for common oils, they weren’t extensively investigated. >It takes about 20 minutes with sporadic simple stirring. Maybe >I’ll try heating and blending with ethanol …
The important point is to ensure the glycerol easily separates, and that the reaction doesn’t go too far, you can add hot water to stop the reaction.. It’s usually monitored using American Oil Chemist’s Society methods for free and combined glycerol, acid value, and hydrolysis valves. >>>Maybe it is because methanol is more reactive? >No, it’s mainly to do with viscosity, mixing, water content, and >ratio of components, obviously the "reaction rate doubles for >every 10C increase" rule also has a significant effect. >The iso-propanol was completely disolved in the cooking oil, so >I think there was something other than mixing involved in getting >it to react…
Sure, but the rate of the reaction is dependent on temperature ( 50-60C about right, ratio of catalyst ( usually given as a mass% of the triglyceride), regardless of the solvent, and 3 moles of methanol,are required for one mole of combined glycerol , thus 4.5 moles= 50% excess If soap isn’t considered a problem then a good procedure is refluxing 0.6% NaOH with 100% excess methanol for 30minutes, and if MAGs are a problem then an additional treatment og ).2% NaoH will take the MAGs to <0.2%. >The important point is to avoid the production of soaps, as >they will give separation problems between the lower glycerol >layer and the upper ester layer, and they represent lost >product. … >there should be no fatty acids to make soap. >Ah, but given the choice of ‘disposing of a lye waste stream’ >and reacting it with a bit more oil to make some soap product … >I think I’ll take the soap as a safer more valuable alternative.
That’s not the choise, the problem is the soaps will increase the dissolution of undesirable impurities in the esters. Bruce Hamilton
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Thinking about it, a lot of this general malaise involved nocturnal nausea and sometimes the mild back pain, but I didn’t really think about it at the time so I concentrated more on the fact that I ‘generally felt ill’. If I were to see a doctor what sort of steps would be taken (eg drugs, follow-ups)? I am one of those people who are reassured by knowing the exact details of what could happen to them! I suspect that my eating has a bit part to play in all this… what would you say is a good eating pattern to aggravate and alleviate reflux? For various reasons I am not eating too well but I won’t go into details right now. Maybe the amount of Coke I drink is relevant! The reason I write right now is that I woke up an hour or two ago feeling sick – more so than usually (actually the frequency of this night nausea occurring has dropped a *lot* since around April, but it wasn’t normally as severe as today) – but after a while I started retching and then the nausea subsided completely and hasn’t returned. I’ve experienced retching on the odd night since symptoms first threatened to appear but never actually brought anything up – why would this be? It has been at night, hence less in the stomach; could it be because the acid is just coming up even further than usual and triggering a reflex of some sort? (I like to keep thinking – takes the mind off the immediate feeling!). The back pain has also returned (and stayed on after the nausea subsided), and there is also some stomach pain and some diarrhoea – that is, it’s all worse than normal, but I do wonder whether it’s partly just a stomach bug. Something else I’ve noticed is that I feel a very slight, almost burning sensation in my oesophagus when I drink the local water (at my term-time residence). I do not notice this at home (I think a lot of people who have come from other areas don’t particularly like the water but I haven’t heard much mention of any issues other than its taste). Someone has suggested that it may be related to high chlorine content in the water; could I be more sensitive to this because reflux has inflamed my oesophagus? 
She was SO right! This goes hand in hand with what the poster below is saying concerning the Atkins diet, a VERY low carb diet. If you’re ingesting a lot of sugar, pasta, bread, rice cut way way back and see if that helps. Eliminating most of the carbs in my life has also given me more energy, joint pain is much improved and my intolerance to heat is vastly improved. Discovering I had diabetes and dealing with it has been the best thing that has ever happened to me. BTW, has anyone tried Nu-Zymes? It’s an enzyme supplement for people with digestive problems. My daughter has had digestive problems since she was a small child. Eating a tiny amount of food can cause her stomach to swell to the point she looks pregnant. She’s never had daily bowl movements. Once a week is *normal* for her. Her stomach hurts ALL the time. I ordered these and she’s been taking 2 per day since the day before Thanksgiving. She emailed me today to tell me she had 3 bowl movements today and 2 yesterday. She was thrilled <lol> I asked if it was helping with the pain and bloating after eating. Quote, "yeah… it surely is =)". I’m praying this is the answer to her problem. 
