The latest data fail to support the hypothesis that a dilute sodium alloy can be used for a Bouveault-Blanc reduction of fatty acid methyl esters (more specifically, methyl stearate) dissolved in toluene with anhydrous ethanol as a proton donor. Given the fact that the intermediates in the Bouveault-Blanc reduction are highly reactive and that it takes 4 sodium atoms per molecule, the low concentration of sodium present in the molten metal alloy may not be enough for the reaction to go to completion.
The ugly fact that there was no evidence of fatty alcohol formation in the gas chromatogram after eight hours of electrolysis leads to an inescapable conclusion: the concept is not viable from a scientific or commercial sense.
I would like to apologize to the RocketHub funders who opted for the illustrated PDF guide to fatty alcohols. The booklet took me longer to research and write than I initially anticipated.
Wildcat Metallurgy recently signed a Cooperative Research and Development Agreement with the Naval Surface Warfare Center – Dahlgren Division, to develop sodium alloys for the synthesis of fatty alcohols.
Electrostatic potential field of 1-dodecanol (lauryl alcohol) molecule generated with Avogadro and edited with GIMP.
The biodiesel recipe card is finished and has been uploaded to the print shop server. The postcards will be going out next week!
Vegetable oil is renewable, nontoxic, and carbon-neutral.
Last Friday I visited a biodiesel refinery in Belvidere, Illinois. Operated by BioVantage Fuels LLC, the plant takes waste vegetable oil from restaurants in the greater Chicago area and converts it to B95 and B100 fuel. The fuel must meet stringent quality standards set by the American Society of Testing and Measurement (ASTM D-6751), which ensures compatibility with diesel engines. The growing supply of biodiesel across America offers great potential not only for fuel. As the cost of extracting petroleum rises, the use of renewable raw materials for making chemicals becomes more economically attractive.
The Belvidere plant is capable of producing millions of gallons of biodiesel every year. It take roughly eighteen hours for a drop of waste vegetable oil to be converted to biodiesel. The chemistry should be familiar to anyone who has made biodiesel. A two-stage process, with acid-catalyzed esterification followed by base-catalyzed transesterication, maximizes the amount of biodiesel which can be extracted from waste vegetable oil. While the process is the same, the reactors and supporting equipment are much larger in scale!
Biodiesel holding tanks and methanol recovery tower.
Biodiesel is a blend of fatty acid methyl esters. For the initial test of the notional modified Bouveault-Blanc reduction, it would be better to use a pure reactant to simplify product analysis. Stearic acid can be converted to methyl stearate using an excess of methanol and a few drops of concentrated sulfuric acid as catalyst. To get the stearic acid into the methanol, the solution must be heated to its boiling point (65°C). Instead of replacing the methanol as it is boiled off, it is less expensive and more environmentally friendly to condense the methanol vapor and re-use it in the reaction.
Refluxing methanol with a round-bottom reaction vessel
In a typical organic laboratory, one would typically employ a round-bottom flask with a condenser for refluxing. However, in the absence of a proper condenser, anything that can cool the methanol vapor will do! As can be seen in the picture, a round-bottom reaction vessel half-filled with ice water can be very effective in condensing the methanol vapor.
The stearic acid initially formed a white opaque slurry with the methanol and a clear colorless liquid when melted. Two hours into the reflux, and the reaction solution has taken on a yellowish-tint (similar to biodiesel). Success?