Sciencemadness Discussion Board

Acetonitrile synth

Jackson - 31-1-2019 at 09:56

I found a paper about the synthesis of acetonitrile from ammoxidation of ethanol with acetaldhyde being an intermediate that is what actually reacts. In the paper, MnO2 is listed as a catalyst. Also the reaction tempatures for the ammoxidation of ethanol are much higher than its boiling point. It also says that the reaction could be performed at a lower tempature. My question is, could I essentially put ethanol, hydrogen peroxide, ammonia solution, and potassium permanganate into a bomb and heat it for a while?

Link to the paper:
http://amsdottorato.unibo.it/5743/1/Federico_Folco_tesi.pdf

unionised - 31-1-2019 at 11:34

Apart from the likelihood of "bomb" being rather too accurate a term for what happens...
It's very unlikely that you would get significant acetonitrile formation in the presence of water.

clearly_not_atara - 31-1-2019 at 16:18

Why do people prefer complicated speculative syntheses rather than the published easy ones?

S.C. Wack - 31-1-2019 at 17:39

The preference appears to be to start threads and often accounts to try to make other people waste their time in response to some esoteric thing pulled from a dark hole, often with added BS.

Jackson - 31-1-2019 at 18:43

Sorry, I just couldn’t find a procedure in the paper I linked.
It also said that it was performed with azetropic ethanol, ammonia gas and air as an oxygen source. The reason why I asked about switching out MnO2 for KMnO4 was because what o read from the paper was that acetaldye was the actual thing reacting in the ammoxidation reaction, and because ethanol could be oxidized to acetaldehyde by KMnO4, with MnO2 being left, I thought that it may be a better option that could help the reaction go along. Also, I Am now thinking that the reaction is supposed to happen in the gas phase as the reaction is heated. I think I would need a pretty good condenser to reflux ethanol at 400c though.

[Edited on 2/1/2019 by Jackson]

Jackson - 31-1-2019 at 18:55

Doh! I am such an idiot. The reaction tempatures most likely refer to the tempature of the catalyst. I think what is supposed to happen is that ethanol is boiled with ammonia and mixed with air where it is then sent over a catalyst bed.

Also after further reading the paper stated (on page 97) that the best catalyst for making acetonitrile from ethanol and ammonia is Cobalt oxide supported by alumina.

[Edited on 2/1/2019 by Jackson]

ninhydric1 - 31-1-2019 at 20:50

Probably easier to go through the standard NH4CH3COO -> acetamide -> acetonitrile method.