Your Questions About Biodiesel Conversion

admin answers:

Waste water? Most biodiesel reactions are sensitive to water and will not proceed if water is present. Biodiesel conversions are sensitive to water because they are usually catalyzed by bases such as NaOH and Na-methoxide . There shouldn’t be any waste water unless it is absorbed through the atmosphere after the reaction has completed. The main byproduct of the transesterification should be glycerine. Glycerine is used in cosmetics and is often converted to glycerol carbonate which has even more uses.

I just checked out daddeeo’s source. There’s no way that NaOH and methanol will react to give sodium methoxide unelss they add an extreme excess of NaOH. Sodium methoxide is extremely extremely reactive and is hella lot stronger of a base than NaOH. This means that the reaction is favored in the reverse direction. Who ever posted that article is mistaken. They think that sodium methoxide is catalyzing the reaction, but its actually the NaOH that is performing the catalysis. If you used the method described in the article you would in fact generate water upon formation of the sodium methoxide but I’m positive this is not the case.
Sodium methoxide reacts violently with water to emit flammable but non toxic gases. When you solubilize NaOH in methanol you are doing just that, solubilizing it, there is no production of sodium methoxide…the rxn runs in the reverse direction. Furthermore the water that is allegedly generated would react with the remaining NaOH and saponify, generating soap. The catalyst in the article is NaOH, not NaOMe.