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Specialty Chemistry Forums => Citizen Chemist => Topic started by: billnotgatez on October 30, 2005, 11:58:28 PM

Title: Ethanol to Ethane or Ethene
Post by: billnotgatez on October 30, 2005, 11:58:28 PM
Could some of my fellow forum members post how they would convert ethanol to ethane or ethene?
It would be nice if the process could be done at room temperature and pressure.

Title: Re:Ethanol to Ethane or Ethene
Post by: Alberto_Kravina on October 31, 2005, 02:11:06 AM
It's possible!

Take a big test tube and put some aluminium oxide (it works as a catalyst) Al2O3 in it. now add some mililiters of ethanol and heat.

    H H
    |  |
H-C-C-O-H  ------Al2O3+ Heat ---->
    |  |
    H H
                H     H
                  \     /
----------->   C=C         + H2O
                  /     \
                H     H


http://www.chemguide.co.uk/organicprops/alkenes/making.html#top
Title: Re:Ethanol to Ethane or Ethene
Post by: billnotgatez on November 01, 2005, 01:48:40 AM
Thank you for the post and the link.
Any other ideas from anyone?
Title: Re:Ethanol to Ethane or Ethene
Post by: Alberto_Kravina on November 03, 2005, 03:51:48 PM
Do you mean another way to make ethene from ethanol or making ethene with other methods?
Title: Re:Ethanol to Ethane or Ethene
Post by: billnotgatez on November 03, 2005, 07:05:37 PM
Currently I am just interested in Ethane or Ethene from Ethanol. Is there more than one approach to this problem? The aluminum oxide procedure may lend itself to solar heat, which is intriguing.
Title: Re:Ethanol to Ethane or Ethene
Post by: billnotgatez on November 03, 2005, 07:21:31 PM
It seems to me that Mike and some of the others could join the fray :)
Title: Re:Ethanol to Ethane or Ethene
Post by: mike on November 03, 2005, 07:32:50 PM
hydroxyl groups are poor leaving groups so reduction of alcohols is rarely done in one step.

You could try tosylating the alcohol (OH) and then reacting with LiAlH4
Title: Re:Ethanol to Ethane or Ethene
Post by: mike on November 03, 2005, 07:37:38 PM
You could possibly dehydrate the alcohol with an acid catalyst. I am not sure how practical this is for you example, you could probably drive the equilibrium by removing product(?)


haha, I just noticed that alberto's link said the same thing :D
Title: Re:Ethanol to Ethane or Ethene
Post by: Alberto_Kravina on November 04, 2005, 01:27:09 PM
Mabye you can make ethane just by adding sodium hydride to ethanol:

C2H6O + NaH -----> C2H6 + NaOH

Beware: You should make it in absenge of water (oh well, a total absence of water is impossible, but If you make this reaction use pure ethanol)

NaH + H2O -----> NaOH + H2(g)
Title: Re:Ethanol to Ethane or Ethene
Post by: GCT on November 04, 2005, 03:59:06 PM
interesting thing about converting ethanol to ethane is on how one would collect the ethane (-88.6C boiling point).  Not an org chem major by the way.
Title: Re:Ethanol to Ethane or Ethene
Post by: Alberto_Kravina on November 05, 2005, 04:24:38 AM
Here is how I would collect the ethane:


http://www.chemguide.co.uk/organicprops/alkenes/making.html#top

(The picture shows how to collect ethene, but It´s the same for ethane)
Title: Re:Ethanol to Ethane or Ethene
Post by: pantone159 on November 05, 2005, 06:14:35 PM
That's a really good website, btw.
Title: Re:Ethanol to Ethane or Ethene
Post by: billnotgatez on November 05, 2005, 06:43:53 PM
On that web site – in the diagram – they have “mineral wool soaked in ethanol”

Why?
What is mineral wool?
Title: Re:Ethanol to Ethane or Ethene
Post by: billnotgatez on November 05, 2005, 07:21:04 PM
When searching on this site for tosylat – I found this entry by Movies

http://www.chemicalforums.com/index.php?board=3;action=display;threadid=850;start=msg7151#msg7151

Title: Re:Ethanol to Ethane or Ethene
Post by: billnotgatez on November 06, 2005, 04:30:17 PM
http://en.wikipedia.org/wiki/Mineral_wool
After reading the above site I sort of understand what mineral wool is.
I wonder if they are using the condition version and why they are soaking mineral wool with the ethanol.

On a separate note, I think I have the alumina (aluminum oxide?) from a ceramics store, but I have to confirm the composition.

Title: Re:Ethanol to Ethane or Ethene
Post by: billnotgatez on November 10, 2005, 06:03:21 AM
http://en.wikipedia.org/wiki/Phosphoric_acid
Concentrated phosphoric (V) acid, H3PO4 seems to be a good catalyst for this conversion as well.