This is not new, but sodium methoxide has been brought up several times lately and is considered a somewhat hard to get reagent. So I thought this should be dragged back up!

Chemically, transesterified biodiesel comprises a mix of mono-alkyl esters of long chain fatty acids. The most common form uses methanol (converted to sodium methoxide) to produce methyl esters (commonly referred to as Fatty Acid Methyl Ester - FAME) as it is the cheapest alcohol available, though ethanol can be used to produce an ethyl ester (commonly referred to as Fatty Acid Ethyl Ester - FAEE) biodiesel and higher alcohols such as isopropanol and butanol have also been used. Using alcohols of higher molecular weights improves the cold flow properties of the resulting ester, at the cost of a less efficient transesterification reaction. A lipid transesterification production process is used to convert the base oil to the desired esters. Any free fatty acids (FFAs) in the base oil are either converted to soap and removed from the process, or they are esterified (yielding more biodiesel) using an acidic catalyst. After this processing, unlike straight vegetable oil, biodiesel has combustion properties very similar to those of petroleum diesel, and can replace it in most current uses.

http://en.wikipedia.org/wiki/Biodiesel
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There are many people making this at home nowadays and there are many websites with recipes, techniques ect. The most common way as stated above is to prepare Sodium Methoxide to catalyse the reaction. Sodium methoxide is a very valuable chem and was previously unavailable due to requiring the reactive and dangerous to handle and transport sodium metal, but the process used by home biodiesel producers. Uses methanol and sodium hydroxide, to deprotonate the alcohol leaving the sodium salt of the conjugate base of methanol (in this case sodium methoxide). It is a reversible reaction so any water present is going to hydrolize the methoxide back into hydroxide/alcohol, to overcome this there are a few OTC methods for home biodiesel producers to pull this off.

• Molecular Sieves,

available from biodiesel supply places like;

Bio Fuel Systems (and many more otc)
http://www.biofuelsystems.com/shop/product_info.php?products_id=297

Base catalyzed transesterification of wild apricot kernel oil for biodiesel production

Biodiesel production

Biodiesel was produced through base (NaOH) catalyzed transesterification
(Freedman et al.,1986), with some modification such
that methoxide prepared by dissolving NaOH pellets into methanol
was treated with molecular sieve (size A3) for 10 h to remove any of
the chemical water produced during reaction of methanol with sodium
hydroxide prior to transesterification. The ratio of oil to methanol
was 1:6. A separate sample of biodiesel was also produced
without using molecular sieve with same catalyst under similar
operating conditions.

http://www.academicjournals.org/AJB/PDF/pdf2009/20Jul/Ullah%20et%20al.pdf

• Dehydrating Agents (Sulfuric Acid in this case)

Advanced vacuum biodiesel process

Reactants :
1. Vegetable Oil
2. Methanol (CH3OH) 98% purity or better.
3. Concentrated Sulfuric acid 93% or better
4. Potassium hydroxide (anhydrous) 85% or better

Process overview

1. Vegetable oil is dried
2. Calculated quantities of methanol and sulfuric acid are mixed and added while recirculating heated oil. Recirculation is continued for at least 60 minutes.
3. Calculated quantities of potassium hydroxide and methanol are mixed and then added while recirculating heated oil. Recirculation is continued for at least 60 minutes.
4. Settling and glycerin removal.
5. Wash test performed
6. Excess methanol is recovered from fuel (recommended option)
7. Biodiesel is then washed and dried.
8. It is then checked for quality.

I think we should be looking into this field for OTC sodium and potassium methoxide and or ethoxide that would prove to be very useful! As many average citizens are producing their own biodiesel in their backyards nowadays the materials they are using are available over the net, or easily found and bought locally.

I will put that method (for producing medium concentration sodium methoxide in methanol) here in case it gets deleted from that site in future. And requires 99% methanol.

Methoxide the easy way

Mixing lye with methanol creates an exothermic reaction, generating heat. It's nasty stuff and it's not easy to mix -- and it must be thoroughly mixed before you use it, with all the lye dissolved. This is a safe and easy way to do it. The disadvantage is that you have to do it in advance, but that's easily arranged.

Take FULL SAFETY PRECAUTIONS when working with methanol, lye and sodium methoxide!

Use a tough, thick, container made of HDPE (High-density Polyethylene -- usually marked "HDPE" on the bottom, with the international code "2"), with a tight stopper and a screw-on lid. Measure out the methanol into the container. Add the required amount of lye -- if you're doing large quantities, add it bit by bit rather than all at once, give the container a swirl in between (replace stopper and lid first). Once it's all added, replace the stopper and the lid, and swirl the mixture about for a few seconds. Then let it stand. Do that a few more times, every few hours or so (at least 4-6 times in all). It will be thoroughly dissolved in 24 hours, or maybe a bit longer.

The proportion of lye to methanol used in making biodiesel is low, particularly with the Foolproof method. If for some reason you're using much higher proportions of lye, then don't do it this way.

Good find Soma,

The problem was stated in that post though. First off the method was a quote from;

Production of sodium and potassium alkoxides
United States Patent 4267396
http://www.freepatentsonline.com/4267396.html

Where they use Calcium Oxide to react with the water produced from the reaction, to form Calcium Hydroxide and pushing the alkoxide formation forward. Calcium oxide (quick lime) is so easily acquired, it should not be done away with. Secondly in the patent they use a surfactant, which makes the reaction times more realistic and keeps the alkoxide in solution while the calcium hydroxide precipitates out which can be decanted off. Looking at the actual experimental you see where the troubles lie!

Example IA(Without Surfactant, or heat)

150 parts of calcium oxide pebbles (about 1/2 inch in size), 40 parts caustic soda flakes, and 262 parts methanol were combined in a reaction vessel fitted with a reflux condenser and stirred with moderate speed at room temperature for 197 hours. The solid material in the reactor was allowed to settle and the supernatant liquid was carefully decanted away from the settled solids. The solution contained 11.76% NaOCH3, 5.33% NaOH, 0.09% Na2CO3, which constitutes a 61.8% yield of NaOCH3.

Example ID(without heat)

Example IA is repeated however with 1% sodium lauryl sulfate. After 144 hours the solution contained 11.6% NaOCH3.

Example IIA(without surfactant)

99 parts methanol, 20 parts caustic soda flakes, and 75 parts calcium oxide, powdered, were combined in an apparatus similar to that in Example I and maintained between 45*C and 60*C for 54 hours with mild agitation. The decanted products were found to contain: 13.04% NaOCH3, 8.36% NaOH and 0.30% Na2CO3 which constitutes a 53.0% yield of Na2OCH3.

Example IIB

Example IIA is repeated however with 2% cetyl pyridinium chloride. After 54 hours the solution contained 22.3% NaOCH3.

Example IVA

18 parts commercial soda flakes, 76 parts calcium oxide and 242 parts ethanol were combined in an apparatus similar to Example I and stirred at room temperature for 24 hours. The product was found to contain 3.05% NaOC2H5, 5.42% NaOH, 0.44%Na2CO3 which shows a 23.8% conversion to sodium ethylate.

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As you can see example IIA would be the most feasible, example IA in excess methanol returns a 12% sodium methylate in methonol solution. So would leave you with 12% Sodium methoxide in methanol (also with 5% NaOH and minor amounts of sodium carbonate). This would be good to reduce the volume and use 'as is' for most purposes, and could be taken and used directly in some synth's. But for other purposes where you need a relatively pure product, you would have to work it up further, or use Example IIA that returns a solid product rather than a solution. For example if the small amounts of sodium carbonate and moderate amounts of sodium hydroxide were not going to hinder your reaction(they generally wont, as alkoxide is a much stronger base and if that is being used a very strong base is required moreso than hydroxide, so at worst hydroxide will deprotonate your target and not be able to do much more than that, which will have no negative outcome. But there is reactions where you would need to remove it). But in most cases just by carefully reducing the volume of methanol preferably under vac, you will be increasing the alkoxide conc! Remove half the volume under gentle heat and you will have roughly a 24% methoxide solution (with 10% NaOH), remove another half = 48% solution (with 20% hydroxide) so on....

The reaction times like 190+ hours seem ridiculous but remember those were at room temperature! So set it and forget it, for three days. Not that bad, as no heat is needed is less dangerous ect, and if you needed a pure product you would want to preform example IIA and return a solid product.

Merck sells either Sodium methylate 'for synthesis' or Sodium Methylate 30% in methanol 'for synthesis', so for most purposes making a solution as above and reducing the volume down about 1/4 will give you a close to 50% conc that should be fine for all synths where the hydroxide will not be a problem (maybe even too strong for some synths, really depends what it is going to be used for).

edit; The procedure for producing a solid, would be as well as the aforementioned products would have a decent amount of calcium hydroxide also. This is not harmful to the methylate and to remove you would add methanol to dissolve only the methylate (and eventually the hydroxide) but dissolving the methoxide quickly in dry methanol and then filtering will make sure most of the sodium and calcium hydroxides are precluded as calcium hydroxide and sodium hydroxide take a lot longer to dissolve into alcohol than sodium methoxide.

I found a reference to making metal alkoxides (eg, Ti, Ni ect) via electrochem using those metals as anodes, but obviously sodium is not used. I am not sure about electrolysis of metal salts or hydroxuides ect

Electrochemical synthesis of metal alkoxides. Prospects of commercial alkoxides production
Abstract  A production method of Ti, Zr, Nb, Ta, Y, Sn, Cu, Ge, Mo, W and some other metals alkoxides at their anode polarization in alcohols (methanol, ethanol, i-propanol, butanol, methoxy-ethanol) in the presence of an electroconductive additive has been developed.
http://www.springerlink.com/content/h66581406803nh17/

Oh you are right! Sorry, that is a nice method its a shame it does not work for methoxide though. But is a nice route all the same!

Silica gel or anhydrous salts forming an hydrate will take water from ethanol, but will not break ethanol's azeotrope AFAIK.

That is very interesting, so it is that simple?

Let me know if I am understanding you correctly, you added CaO (you say lime, but I figure this is what you meant?) to ethanol in excess, and then added NaOH allowing it to sit for a while, so it could finish the reaction of: EtOH CaO + NaOH => Ca(OH)2 + NaOEt  Once the reaction was thought to be complete, the liquid layer was added to acetone to precipitate sodium ethoxide, and leave a acetone/ethanol solution above?

If CaCl2 was present, NaCl could have formed as well, are you sure what you were looking at wasn't from something like that? but was indeed Sodium Ethoxide?

Interesting, this makes it seem pretty easy to make...  You ought to leave the CaO in excess while the NaOH is added since a product of NaOH + EtOH => NaOEt + H2O --- this would allow the H2O that forms to react with the CaO and be taken out of the reaction, driving the reaction further to the right, giving better yields. Thanks for the patent, I had missed that.

What is NaOEt really used for? I know it has uses, like this...http://en.wikipedia.org/wiki/Reissert_indole_synthesis
but I don't know of many other uses.

After modifying a fridge compressor into a vac pump I decided to give sodium ethoxide a little more scientific approach. 150ml denatured EtOH dried for 24hrs with 50g 3A sieves (nuked 2x3mins on medium). Sieves filtered out and the ethanol and 35g NaOH were added to a 250ml RBF with drying tube and stirbar, heated at 70c for 1hr. Yellow solution was vac filtered to remove NaOH. 80ml dry acetone added to mother liquor and the precipitate vac filtered, washed with 50ml kerosene to remove acetone. Dried for a few mins under vac then weighed (3.7g white powder) and put into dessicator. From my initial experiments and patent info it would seem around 60c is the temperature to aim at with a higher temp resulting in a more orange solution, and everything should be as anhydrous as possible. The yield in this case isn't fantastic but with some optimizations it could be a lot better. For starters a huge excess of NaOH is used because i'm not entirely sure how much will be consumed, the NaOH filter cake could probably be rinsed with dry hot ethanol to recover a little more ethoxide, I didn't complete the whole process as quickly as it should be yield is lost all the time to moisture and CO2. Second trial involved lime dried ethanol and the yield was 3.8g from ~60ml EtOH and 35g NaOH so the first one probably wasn't dry enough.

I'm open to any ideas or improvements!

Another question would the pores of molecular sieves be damaged in the highly basic solution, getting banged around by the stirbar?

Why dont you try Organikums method, that was posted at SM;

A sep-funnel or anything else with an outlet (faucet) at the bottom is filled to 1/3rd with NaOH pellets and filled full with EtOH of 92% or of higher concentration (preferred). This sits for at least half an hour and then about 1/4th of the liquid at the bottom is withdraw very slowly. Then the rest is withdraw. This rest consists of EtOH which contains sodium ethoxide. Distilled to yield anhydrous EtOH, sodium ethoxide is left back which can be used to dry more EtOH so desired.
If the alcohol is pre-dried with anhydrous CuSO4 which was dehydrated at 300°C+ much less NaOH is needed. This pre-drying takes time though, the longer the better in special if no stirring is applied.
If the ethoxide is whats desired the alcohol should be left in the vessel for longer time, if bigger amounts are wanted it is favorable to withdraw alcohol/ethoxide from top and water/NaOH/alc from bottom and to refill alcohol. This is an almost continous process then.

Tried and true.

https://sciencemadness.org/talk/viewthread.php?tid=2656