Serybva
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Auto-ignition temperature
One way to make acetaldehyde is to oxidize ethanol vapors over red hot copper wire, the copper temperature is said, in a paper I found, to be around
500-600° which corresponds to "red hot" state.
However auto-ignition temperature of ethanol is 365°, so why ethanol vapors don't ignite upon contact with the copper?
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B(a)P
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Presumably you exclude oxygen from the reaction.
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Texium
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Thread Moved
13-4-2022 at 05:39 |
Serybva
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Actually no, oxygen is required for the reaction to take place and there is videos on youtube that show the reaction by just suspending a red hot
penny in a beaker with some ethanol in it
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unionised
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If the ratio of air to fuel vapour is far enough from ideal then you won't get ignition.
More importantly, you can do that reaction without air.
https://en.wikipedia.org/wiki/Acetaldehyde#Dehydrogenation_o...
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Serybva
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Thanks !
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reactofurnace
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Would you dissolve the acetaldehyde produced in water?
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Fantasma4500
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supposedly air-fuel ratio, as most fuels- acetylene and ethylene oxide excluded as they can "burn" in 100% concentration (more like, detonate sorta)
im having some ideas of coating sand or pebbles in platinum and then pumping air into EtOH/Pt catalyst, this idea i came to when another user
mentioned having some Pd/C laying around
if the oxidation can happen directly- presumably at quite low temperature inside of the ethanol you could end up with an extremely safe reaction- this
reaction is especially dangerous with methanol as it more oftenly ignites than ethanol, benzyl alcohol may also be oxidized like this but the boiling
point makes it a more difficult operation
avoid using acetone as this will form deadly toxic ketene- a fellow chemist did run a ketene lamp without knowing anything about ketene, no windows
open or anything and hes still around, but its potentially deadly scenario
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